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Sample records for permanent iodine-125 brachytherapy

  1. [Permanent iodine-125 implants brachytherapy: results after 10 years of experience in Liège University Hospital].

    PubMed

    Hermesse, J; Nickers, P; Reul, O; Coucke, P

    2014-01-01

    Permanent implant iodine-125 brachytherapy is an attractive treatment option for men with localized prostate cancer and is an alternative approach to radical prostatectomy. Overall survival and biochemical relapse free survival are similar with both treatments but the toxicity is different. More potency preservation, less incontinence and one day hospitalisation are attractive for the patient with brachytherapy. On the other side, pre-existing obstructive or irritative urinary symptoms at baseline have to guide the patient to a surgical approach. A patient has to be able to select one of these two therapeutic opportunities through a complete transparent information. In this paper, we related our permanent implant iodine-125 brachytherapy experience. Overall survival, biochemical relapse free survival and registred toxicity are similar to those published in the literature.

  2. Permanent Iodine-125 Interstitial Planar Seed Brachytherapy for Close or Positive Margins for Thoracic Malignancies

    SciTech Connect

    Mutyala, Subhakar; Stewart, Alexandra; Khan, Atif J.; Cormack, Robert A.; O'Farrell, Desmond; Sugarbaker, David; Devlin, Phillip M.

    2010-03-15

    Purpose: To assess toxicity and outcome following permanent iodine-125 seed implant as an adjunct to surgical resection in cases of advanced thoracic malignancy. Methods and Materials: An institutional review board-approved retrospective review was performed. Fifty-nine patients were identified as having undergone thoracic brachytherapy seed implantation between September 1999 and December 2006. Data for patient demographics, tumor details, and morbidity and mortality were recorded. Results: Fifty-nine patients received 64 implants. At a median follow-up of 17 months, 1-year and 2-year Kaplan-Meier rates of estimated overall survival were 94.1% and 82.0%, respectively. The 1-year and 2-year local control rates were 80.1% and 67.4%, respectively. The median time to develop local recurrence was 11 months. Grades 3 and 4 toxicity rates were 12% at 1 year. Conclusions: This review shows relatively low toxicity for interstitial planar seed implantation after thoracic surgical resection. The high local control results suggest that an incomplete oncologic surgery plus a brachytherapy implant for treating advanced thoracic malignancy merit further investigation.

  3. Prostate-Specific Antigen Bounce After Permanent Iodine-125 Prostate Brachytherapy-An Australian Analysis

    SciTech Connect

    Zwahlen, Daniel R.; Smith, Ryan; Andrianopoulos, Nick; Matheson, Bronwyn; Royce, Peter; Millar, Jeremy L.

    2011-01-01

    Purpose: To report on prostate-specific antigen (PSA) 'bounces' after {sup 125}I prostate brachytherapy to review the relationship to biochemical control and correlate both clinical and dosimetric variables. Methods and Materials: We analyzed 194 hormone-naive patients with a follow-up of {>=}3 years. Four bounce definitions were applied: an increase of {>=}0.2 ng/mL (definition I), {>=}0.4 ng/mL (definition II), {>=}15% (definition III), and {>=}35% (definition IV) of a previous value with spontaneous return to the prebounce level or lower. Results: Using definition I, II, III, and IV, a bounce was detected in 50%, 34%, 11%, and 9% of patients, respectively. The median time to onset was 14-16 months, the duration was 12-21.5 months, and the magnitude of the increase was 0.5-2 ng/mL. A magnitude of >2 ng/mL, fulfilling the criteria for biochemical failure (BF) according to the American Society for Therapeutic Radiology and Oncology Phoenix definition, was detected in 11.3%, 16.9%, 47.6%, and 50% using definitions I, II, III, and IV, respectively; 11 patients (5.7%) had true BF. The PSA bounces occurred earlier than BF (p < 0.001). The prediction of BF remains controversial and is probably unrelated to biochemical control. The only statistically significant factor predictive of a PSA bounce was younger age (definitions I and II). Conclusion: PSA bounces are common after brachytherapy. All definitions resulted in a high number of false-positive calls for BF during the first 2 years. The definition of an increase of {>=}0.2 ng/mL should be preferred because of the lowest number of false-positive results for BF. Patients experiencing a PSA bounce during the first 2 years after brachytherapy should undergo surveillance every 3-6 months. Additional investigations are recommended for elevated postimplant PSA levels that have not corrected by 3 years of follow-up.

  4. Phase I Trial of Gross Total Resection, Permanent Iodine-125 Brachytherapy, and Hyperfractionated Radiotherapy for Newly Diagnosed Glioblastoma Multiforme

    SciTech Connect

    Chen, Allen M.; Chang, Susan; Pouliot, Jean; Sneed, Penny K.; Prados, Michael D.; Lamborn, Kathleen R.; Malec, Mary K.; McDermott, Michael W.; Berger, Mitchell S.; Larson, David A.

    2007-11-01

    Purpose: To evaluate the feasibility of gross total resection and permanent I-125 brachytherapy followed by hyperfractionated radiotherapy for patients with newly diagnosed glioblastoma. Methods and Materials: From April 1999 to May 2002, 21 patients with glioblastoma multiforme were enrolled on a Phase I protocol investigating planned gross total resection and immediate placement of permanent I-125 seeds, followed by postoperative hyperfractionated radiotherapy to a dose of 60 Gy at 100 cGy b.i.d., 5 days per week. Median age and Karnofsky performance status were 50 years (range, 32-65 years) and 90 (range, 70-100), respectively. Toxicity was assessed according to Radiation Therapy Oncology Group criteria. Results: Eighteen patients completed treatment according to protocol. The median preoperative tumor volume on magnetic resonance imaging was 18.6 cm{sup 3} (range, 4.4-41.2 cm{sup 3}). The median brachytherapy dose measured 5 mm radially outward from the resection cavity was 400 Gy (range, 200-600 Gy). Ten patients underwent 12 reoperations, with 11 of 12 reoperations demonstrating necrosis without evidence of tumor. Because of high toxicity, the study was terminated early. Median progression-free survival and overall survival were 57 and 114 weeks, respectively, but not significantly improved compared with historical patients treated at University of California, San Francisco, with gross total resection and radiotherapy without brachytherapy. Conclusions: Treatment with gross total resection and permanent I-125 brachytherapy followed by hyperfractionated radiotherapy as performed in this study results in high toxicity and reoperation rates, without demonstrated improvement in survival.

  5. Accurate and efficient detection of pulmonary seed embolization in prostate iodine-125 permanent brachytherapy with a collimated gamma scintillation survey meter.

    PubMed

    Chen, Qin-Sheng; Blair, Henry F

    2003-05-01

    Pulmonary seed embolization is frequently observed in permanent prostate brachytherapy. Postoperative chest radiographic examination does not always detect seed embolization. To overcome this deficiency, a low energy gamma scintillation survey meter was converted to a seed-migration detector by adding a cone-shaped single-hole collimation cap to the window end of the scintillation probe. The response functions of the seed-migration detector to iodine-125 (I-125) for different source-to-detector distances in air and in water were measured. The spatial discrimination power of the survey meter, represented by the full width at half maximum measured in water, is typically improved from more than 7 cm to about 3 cm. Seventy-nine patients with I-125 implantation were scanned with the seed-migration detector at the patients' 30-day postevaluation visit. Fifteen patients showed single-seed embolization to the chest region and four patients displayed two-seed embolization. In other words, 24% of the patients present with embolized seeds. The detection accuracy of each patient was validated by a comprehensive investigation procedure. The comprehensive investigation consists of reviewing the patient's treatment history, orally questioning the patient for possible seed loss via the urethra route outside the hospital, examining all available chest radiographs before and after the seed implantation, and counting the seeds on the postevaluation CT scans. In comparison, examinations relying only on the analysis of postoperative chest radiographs yielded a false-positive detection in four patients and a false-negative detection in two patients. Another advantage of the seed-migration detector is that multiple seed-migration scans can be performed without exposing the patient to any additional radiation, for this device is a passive detector. Our clinical implementation also demonstrated that the seed-migration detector is a convenient and cost-effective method. As a result of this

  6. Urinary and Rectal Toxicity Profiles After Permanent Iodine-125 Implant Brachytherapy in Japanese Men: Nationwide J-POPS Multi-institutional Prospective Cohort Study

    SciTech Connect

    Ohashi, Toshio; Yorozu, Atsunori; Saito, Shiro; Tanaka, Nobumichi; Katayama, Norihisa; Kojima, Shinsuke; Maruo, Shinichiro; Kikuchi, Takashi; Dokiya, Takushi; Fukushima, Masanori; Yamanaka, Hidetoshi

    2015-09-01

    Purpose: To assess, in a nationwide multi-institutional cohort study begun in 2005 and in which 6927 subjects were enrolled by 2010, the urinary and rectal toxicity profiles of subjects who enrolled during the first 2 years, and evaluate the toxicity profiles for permanent seed implantation (PI) and a combination therapy with PI and external beam radiation therapy (EBRT). Methods and Materials: Baseline data for 2339 subjects out of 2354 patients were available for the analyses. Toxicities were evaluated using the National Cancer Institute's Common Terminology Criteria for Adverse Events, and the International Prostate Symptom Scores were recorded prospectively until 36 months after radiation therapy. Results: Grade 2+ acute urinary toxicities developed in 7.36% (172 of 2337) and grade 2+ acute rectal toxicities developed in 1.03% (24 of 2336) of the patients. Grade 2+ late urinary and rectal toxicities developed in 5.75% (133 of 2312) and 1.86% (43 of 2312) of the patients, respectively. A higher incidence of grade 2+ acute urinary toxicity occurred in the PI group than in the EBRT group (8.49% vs 3.66%; P<.01). Acute rectal toxicity outcomes were similar between the treatment groups. The 3-year cumulative incidence rates for grade 2+ late urinary toxicities were 6.04% versus 4.82% for the PI and the EBRT groups, respectively, with no significant differences between the treatment groups. The 3-year cumulative incidence rates for grade 2+ late rectal toxicities were 0.90% versus 5.01% (P<.01) for the PI and the EBRT groups, respectively. The mean of the postimplant International Prostate Symptom Score peaked at 3 months, but it decreased to a range that was within 2 points of the baseline score, which was observed in 1625 subjects (69.47%) at the 1-year follow-up assessment. Conclusions: The acute urinary toxicities observed were acceptable given the frequency and retention, and the late rectal toxicities were more favorable than those of other studies.

  7. Complications associated with preoperative radiation therapy and Iodine-125 brachytherapy for localized prostatic carcinoma

    SciTech Connect

    Flanigan, R.C.; Patterson, J.; Mendiondo, O.A.; Gee, W.F.; Lucas, B.A.; McRoberts, J.W.

    1983-08-01

    Twenty-five consecutive patients with localized adenocarcinoma of the prostate treated with 1,050 rad preoperative radiation therapy and Iodine-125 seed brachytherapy are reviewed. Significant long-term postoperative complications included radiation cystitis (12%), radiation proctitis (4%), genital and leg edema (12%), stress incontinence (8%), total incontinence (4%), and impotence (26%). Complications occurred in 75 per cent of patients who received additional postoperative radiation. Improved staging with CT scan, lymphangiography, and Chiba needle biopsy of any possibly abnormal lymph nodes provided excellent preoperative staging with only 1 patient (6%) upstaged at surgery to Stage D1.

  8. Influence of Dose on Risk of Acute Urinary Retention After Iodine-125 Prostate Brachytherapy

    SciTech Connect

    Roeloffzen, Ellen M.A.; Battermann, Jan J.; Deursen, Marijke J.H. van; Monninkhof, Evelyn M.; Visscher, Mareije I.; Moerland, Marinus A.; Vulpen, Marco van

    2011-07-15

    Purpose: To assess the influence of dose on the risk of acute urinary retention (AUR) after iodine-125 prostate brachytherapy. Methods and Materials: Between January 2005 and December 2008, 714 consecutive patients with localized prostate cancer were treated with iodine-125 prostate brachytherapy at our department. All patients completed four imaging studies: magnetic resonance imaging before and 4 weeks after treatment and intraoperative three-dimensional transrectal ultrasonography before and after implantation. The development of AUR was prospectively recorded. The evaluated treatment and dosimetric parameters included prostate volume, number of needles and seeds used, intra- and postoperative prostate edema, percentage of prostate volume receiving 100%, 150%, and 200% of the prescribed dose to the prostate, minimal dose received by 90% of the prostate volume, and percentage of the urethra receiving 100%, 150%, and 200% of the prescribed dose. Logistic regression analysis was used to examine which factors were associated with AUR. Results: Of the 714 patients, 57 (8.0%) developed AUR. On univariate analysis, the following treatment and dosimetric factors were significantly associated with AUR: International Prostate Symptom Score (odds ratio [OR], 2.07, per 10-point increase), preimplant prostate volume (OR, 1.06), postimplant prostate volume (OR, 1.04), number of needles used (OR, 1.09), and number of seeds used (OR, 1.03). On multivariate analysis, the only independent predictive factors for AUR were pretreatment prostate volume (OR, 1.05) and International Prostate Symptom Score (OR, 1.76, per 10-point increase). Patients with a pretreatment prostate volume >35 cm{sup 3} had a 10.4% risk of developing AUR compared with 5.4% for those with a prostate volume of {<=}35 cm{sup 3}. No association was found between any of the dosimetric parameters and the development of AUR. Conclusion: The radiation dose, within the range studied, did not influence the risk of AUR

  9. Survival of patients with advanced pancreatic cancer after iodine125 seeds implantation brachytherapy

    PubMed Central

    Han, Quanli; Deng, Muhong; Lv, Yao; Dai, Guanghai

    2017-01-01

    Abstract Background: Brachytherapy with iodine125-labeled seeds (125I-seeds) implantation is increasingly being used to treat tumors because of its positional precision, minimal invasion, least damage to noncancerous tissue due to slow and continuous release of radioactivity and facilitation with modern medical imaging technologies. This study evaluates the survival and pain relief outcomes of the 125I-seeds implantation brachytherapy in advanced pancreatic cancer patients. Methods: Literature search was carried out in multiple electronic databases (Google Scholar, Embase, Medline/PubMed, and Ovid SP) and studies reporting I125 seeds implantation brachytherapy in pancreatic cancer patients with unresectable tumor were selected by following predetermined eligibility criteria. Random effects meta-analysis was performed to achieve inverse variance weighted effect size of the overall survival rate after the intervention. Sensitivity and subgroups analyses were also carried out. Results: Twenty-three studies (824 patients’ data) were included in the meta-analysis. 125I-seeds implantation brachytherapy alone was associated with 8.98 [95% confidence interval (CI): 6.94, 11.03] months (P < 0.00001) overall survival with 1-year survival of 25.7 ± 9.3% (mean ± standard deviation; SD) and 2-year survival was 17.9 ± 8.6% (mean ± SD). In stage IV pancreatic cancer patients, overall survival was 7.13 [95% CI: 4.75, 9.51] months (P < 0.00001). In patients treated with 125I-seeds implantation along with 1 or more therapies, overall survival was 11.75 [95% CI: 9.84, 13.65] months (P < 0.00001) with 1-year survival of 47.4 ± 22.75% (mean ± SD) and 2-year survival was 16.97 ± 3.1% (mean ± SD). 125I-seeds brachytherapy was associated with relief of pain in 79.7 ± 9.9% (mean ± SD) of the patients. Conclusions: Survival of pancreatic cancer patients after 125I-seeds implantation brachytherapy is found to be 9 months

  10. A Phase III Randomized Trial of the Timing of Meloxicam With Iodine-125 Prostate Brachytherapy

    SciTech Connect

    Crook, Juanita; Patil, Nikhilesh; Wallace, Kris; Borg, Jette; Zhou, David; Ma, Clement; Pond, Greg

    2010-06-01

    Purpose: Nonsteroidal anti-inflammatory medication is used to reduce prostate edema and urinary symptoms following prostate brachytherapy. We hypothesized that a cyclooxygenase-2 (COX-2) inhibitor regimen started 1 week prior to seed implant might diminish the inflammatory response, thus reducing edema, retention rates, and symptom severity. Methods and Materials: From March 2004 to February 2008, 316 men consented to an institutional review board-approved randomized study of a 4-week course of meloxicam, 7.5 mg orally twice per day, starting either on the day of implant or 1 week prior to implant. Brachytherapy was performed using iodine-125 seeds and was preplanned and performed under transrectal ultrasound (TRUS) and fluoroscopic guidance. Prostate volume obtained by MR imaging at 1 month was compared to baseline prostate volume obtained by TRUS planimetry and expressed as an edema factor. The trial endpoints were prostate edema at 1 month, International Prostate Symptom Score (IPSS) questionnaire results at 1 and 3 months, and any need for catheterization. Results: Results for 300 men were analyzed. Median age was 61 (range, 45-79 years), and median TRUS prostate volume was 35.7 cc (range, 18.1-69.5 cc). Median IPSS at baseline was 5 (range, 0-24) and was 15 at 1 month, 16 at 3 months, and 10 at 6 months. Catheterization was required for 7% of patients (6.2% day 0 arm vs. 7.9% day -7 arm; p = 0.65). The median edema factor at 1 month was 1.02 (range, 0.73-1.7). 1.01 day 0 arm vs. 1.05 day -7 arm. Baseline prostate volume remained the primary predictor of postimplant urinary retention. Conclusions: Starting meloxicam 1 week prior to brachytherapy compared to starting immediately after the procedure did not reduce 1-month edema, improve IPSSs at 1 or 3 months, or reduce the need for catheterization.

  11. Iodine-125 Interstitial Brachytherapy for Pediatric Desmoid-Type Fibromatosis of the Head and Neck: A Case Report.

    PubMed

    Wu, Wen-Jie; Guo, Hua-Qiu; Yu, Guang-Yan; Zhang, Jian-Guo

    2017-04-01

    Desmoid-type fibromatosis (DF) is a locally aggressive benign soft tissue tumor. It is rarely observed in the head and neck region and is particularly uncommon in the parotid gland. This report describes the case of a 32-month-old girl with DF of the head and neck. The tumor was resected with gross residual tumors. Recurrence occurred 3 months later and then the patient was treated with iodine-125 interstitial brachytherapy. The tumor was completely absent 6 months after brachytherapy. No recurrence was found 60 months after brachytherapy during follow-up. No severe toxicities or growth abnormalities were observed. Very-low-dose rate brachytherapy as the sole modality could be a reasonable alternative for the treatment of inoperable DF of the head and neck, which avoids the risk of cosmetic deformity caused by surgery, especially in pediatric patients. In addition, long-term follow-up is recommended.

  12. Outcomes of Iodine-125 Plaque Brachytherapy for Uveal Melanoma With Intraoperative Ultrasonography and Supplemental Transpupillary Thermotherapy

    SciTech Connect

    Badiyan, Shahed N.; Rao, Rajesh C.; Apicelli, Anthony J.; Acharya, Sahaja; Verma, Vivek; Garsa, Adam A.; DeWees, Todd; Speirs, Christina K.; Garcia-Ramirez, Jose; Esthappan, Jacqueline; Grigsby, Perry W.; Harbour, J. William

    2014-03-15

    Purpose: To assess the impact on local tumor control of intraoperative ultrasonographic plaque visualization and selective application of transpupillary thermotherapy (TTT) in the treatment of posterior uveal melanoma with iodine-125 (I-125) episcleral plaque brachytherapy (EPB). Methods and Materials: Retrospective analysis of 526 patients treated with I-125 EPB for posterior uveal melanoma. Clinical features, dosimetric parameters, TTT treatments, and local tumor control outcomes were recorded. Statistical analysis was performed using Cox proportional hazards and Kaplan-Meier life table method. Results: The study included 270 men (51%) and 256 women (49%), with a median age of 63 years (mean, 62 years; range, 16-91 years). Median dose to the tumor apex was 94.4 Gy (mean, 97.8; range, 43.9-183.9) and to the tumor base was 257.9 Gy (mean, 275.6; range, 124.2-729.8). Plaque tilt >1 mm away from the sclera at plaque removal was detected in 142 cases (27%). Supplemental TTT was performed in 72 patients (13.7%). One or 2 TTT sessions were required in 71 TTT cases (98.6%). After a median follow-up of 45.9 months (mean, 53.4 months; range, 6-175 months), local tumor recurrence was detected in 19 patients (3.6%). Local tumor recurrence was associated with lower dose to the tumor base (P=.02). Conclusions: Ultrasound-guided plaque localization of I-125 EPB is associated with excellent local tumor control. Detection of plaque tilt by ultrasonography at plaque removal allows supplemental TTT to be used in patients at potentially higher risk for local recurrence while sparing the majority of patients who are at low risk. Most patients require only 1 or 2 TTT sessions.

  13. Brachytherapy of recurrent malignant brain tumors with removable high-activity iodine-125 sources

    SciTech Connect

    Gutin, P.H.; Phillips, T.L.; Wara, W.M.; Leibel, S.A.; Hosobuchi, Y.; Levin, V.A.; Weaver, K.A.; Lamb, S.

    1984-01-01

    Thirty-seven patients harboring recurrent malignant primary or metastatic brain tumors were treated by 40 implantations of high-activity iodine-125 (/sup 125/I) sources. All patients had been treated with irradiation and most had been treated with chemotherapeutic agents, primarily nitrosoureas. Implantations were performed using computerized tomography (CT)-directed stereotaxy; /sup 125/I sources were held in one or more afterloaded catheters that were removed after the desired dose (minimum tumor dose of 3000 to 12,000 rads) had been delivered. Patients were followed with sequential neurological examinations and CT scans. Results of 34 implantation procedures were evaluable: 18 produced documented tumor regression (response) for 4 to 13+ months; five, performed in deteriorating patients, resulted in disease stability for 4 to 12 months. The overall response rate was 68%. In 11 patients, implantation did not halt clinical deterioration. At exploratory craniotomy 5 to 12 months after implantation, focal radiation necrosis was documented in two patients whose tumor had responded initially and then progressed, and in three patients whose disease had progressed initially (four glioblastomas, one anaplastic astrocytoma); histologically identifiable tumor was documented in two of these patients. All improved after resection of the focal necrotic mass and are still alive 10, 15, 19, 24, and 25 months after the initial implantation procedure; only one patient has evidence of tumor regrowth. The median follow-up period after implantation for the malignant glioma (anaplastic astrocytoma and glioblastoma multiforme) group is 9 months, with 48% of patients still surviving. While direct comparison with the results of chemotherapy is difficult, results obtained in this patient group with interstitial brachytherapy are probably superior to results obtained with chemotherapy.

  14. Early treatment of complex located pediatric low-grade gliomas using iodine-125 brachytherapy alone or in combination with microsurgery.

    PubMed

    Kunz, Mathias; Nachbichler, Silke B; Ertl, Lorenz; Fesl, Gunther; Egensperger, Rupert; Niyazi, Maximilian; Schmid, Irene; Tonn, Joerg Christian; Peraud, Aurelia; Kreth, Friedrich Wilhelm

    2016-03-01

    To analyze efficacy, functional outcome, and treatment toxicity of low-dose rate I-125 brachytherapy (SBT) alone or in combination with best safe resection (in case of larger tumor volumes) as first-line treatment for pediatric low-grade gliomas (PLGGs) not suitable for complete resection. Consecutively treated (2000-2014) complex located circumscribed WHO grade I/II PLGGs were included. For small tumors (≤4 cm in diameter) SBT alone was performed; for larger tumors best safe resection and subsequent SBT was chosen. Temporary Iodine-125 seeds were used (median reference dose: 54 Gy). Treatment response was estimated with the modified MacDonald criteria. Analysis of functional outcome included ophthalmological, endocrinological and neurological evaluation. Survival was analyzed with the Kaplan-Meier method. Prognostic factors were obtained from proportional hazards models. Toxicity was categorized according to the Common Terminology Criteria for Adverse Events. Fifty-eight patients were included treated either with SBT alone (n = 39) or with SBT plus microsurgery (n = 19). Five-year progression-free survival was 87%. Two patients had died due to tumor progression. Among survivors, improvement/stabilization/deterioration of functional deficits was seen in 20/14/5 patients, respectively. Complete/partial response had beneficial impact on functional scores (P = 0.02). The 5-year estimated risk to receive adjuvant radiotherapy/chemotherapy was 5.2%. The overall early (delayed) toxicity rate was 8.6% (10.3%), respectively. No permanent morbidity occurred. In complex located PLGGs, early SBT alone or combined with best safe resection preserves/improves functional scores and results in tumor control rates usually achieved with complete resection. Long-term analysis is necessary for confirmation of these results.

  15. SU-E-T-12: A Comparative Dosimetric Study of Pre and Post Prostate Iodine-125 Permanent Seed Implants

    SciTech Connect

    Liu, X; Rahimian, J; Goy, B; Cosmatos, H; Qian, Y

    2015-06-15

    Purpose: Post-implant dosimetry has become the gold standard for prostate implant evaluation. The goal of this research is to compare the dosimetry between pre-plan and post-plan in permanent prostate seed implant brachytherapy. Methods: A retrospective study of 91 patients treated with Iodine-125 prostate seed implant between year 2012∼2014 were performed. All plans were created using a VariSeed 8.0 planning system. Pre-plan ultrasound images were acquired using 0.5 cm slice thickness. Post-plan CT images acquired about 1–4 weeks after implant, fused with the preplan ultrasound images. The prostate and urethra contours were generated using the fusion of ultrasound and CT images. Iodine-125 seed source activities varied between 0.382 to 0.414 mCi per seed. The loading patterns varied slightly between patients depending on the prostate size. Statistical analysis of pre and post plans for prostate and urethra volumes, V100%, V150% and D90, and urethra D10 were performed and reported. Results: The pre and post implant average prostate size was 36.90cc vs. 38.58cc; V100% was 98.33% vs. 96.89%; V150% was 47.09% vs. 56.95%; D90 was 116.35Gy vs. 116.12Gy, urethra volume was 1.72cc vs. 1.85cc, urethra D10% was 122.0% vs. 135.35%, respectively. There was no statistically significant difference between the pre and post-plan values for D90(p-value=0.43). However, there are significant differences between other parameters most likely due to post surgical edema; prostate size (p-value= 0.00015); V100% (p-value=3.7803E-07); V150% (p-value=1.49E-09); urethra volume (p-value= 2.77E-06); Urethra D10 (p-value=7.37E-11). Conclusion: The post-plan dosimetry using CT image set showed similar D90 dose coverage to the pre-plan using the ultrasound image dataset. The study showed that our prostate seed implants have consistently delivered adequate therapeutic dose to the prostate while sparing urethra. Future studies to correlate dose versus biochemical response using patients’ PSA

  16. Visual Acuity, Contrast Sensitivity and Color Vision Three Years After Iodine-125 Brachytherapy for Choroidal and Ciliary Body Melanoma

    PubMed Central

    Tsui, Irena; Beardsley, Robert M; McCannel, Tara A; Oliver, Scott C; Chun, Melissa W; Lee, Steve P; Chow, Phillip E; Agazaryan, Nzhde; Yu, Fei; Straatsma, Bradley R

    2015-01-01

    Purpose : To report visual acuity, contrast sensitivity and color vision prior to, 1 year after, 2 years after and 3 years after iodine-125 brachytherapy for choroidal and ciliary body melanoma (CCM). Design : Prospective interventional case series. Participants : Thirty-seven patients (37 eyes) with CCM. Methods : Patients had best-corrected Early Treatment Diabetic Retinopathy Study (ETDRS) visual acuity, Pelli-Robson contrast sensitivity and Hardy-Rand-Rittler color vision measurement; comprehensive ophthalmology examination; optical coherence tomography; and ultrasonography at baseline prior to, 1 year after, 2 years after and 3 years after I-125 brachytherapy. Main Outcome Measures : Visual acuity, contrast sensitivity and color vision prior to, 1 year after, 2 years after and 3 years after brachytherapy. Results : Nineteen (19) men and 18 women with mean age of 58 years (SD 13, range 30-78) prior to, 1 year after, 2 years after and 3 years after brachytherapy had mean best-corrected visual acuity of 77 letters (20/32), 65 letters (20/50), 56 letters (20/80) and 47 letters (20/125); contrast sensitivity of 30, 26, 22 and 19 letters; color vision of 26, 20, 17 and 14 test figures, respectively. Decrease in visual acuity, contrast sensitivity and color vision was statistically significant from baseline at 1 year, 2 years, and 3 years after brachytherapy. Decreased acuity at 3 years was associated with mid-choroid and macula melanoma location, ≥ 4.1 mm melanoma height, radiation maculopathy and radiation optic neuropathy. Conclusion : 1, 2 and 3 years after brachytherapy, eyes with CCM had significantly decreased visual acuity, contrast sensitivity and color vision. PMID:26312123

  17. Ocular Response of Choroidal Melanoma With Monosomy 3 Versus Disomy 3 After Iodine-125 Brachytherapy

    SciTech Connect

    Marathe, Omkar S.; Wu, Jeffrey; Lee, Steve P.; Yu Fei; Burgess, Barry L.; Leu Min; Straatsma, Bradley R.; McCannel, Tara A.

    2011-11-15

    Purpose: To report the ocular response of choroidal melanoma with monosomy 3 vs. disomy 3 after {sup 125}I brachytherapy. Methods and Materials: We evaluated patients with ciliochoroidal melanoma managed with fine needle aspiration biopsy immediately before plaque application for {sup 125}I brachytherapy between January 1, 2005 and December 31, 2008. Patients with (1) cytopathologic diagnosis of melanoma, (2) melanoma chromosome 3 status identified by fluorescence in situ hybridization, and (3) 6 or more months of follow-up after brachytherapy were sorted by monosomy 3 vs. disomy 3 and compared by Kruskal-Wallis test. Results: Among 40 ciliochoroidal melanomas (40 patients), 15 had monosomy 3 and 25 had disomy 3. Monosomy 3 melanomas had a median greatest basal diameter of 12.00 mm and a median tumor thickness of 6.69 mm before brachytherapy; at a median of 1.75 years after brachytherapy, median thickness was 3.10 mm. Median percentage decrease in tumor thickness was 48.3%. Disomy 3 melanomas had a median greatest basal diameter of 10.00 mm and median tumor thickness of 3.19 mm before brachytherapy; at a median of 2.00 years after brachytherapy, median tumor thickness was 2.37 mm. The median percentage decrease in tumor thickness was 22.7%. Monosomy 3 melanomas were statistically greater in size than disomy 3 melanomas (p < 0.001) and showed a greater decrease in tumor thickness after brachytherapy (p = 0.006). Conclusion: In this study, ciliochoroidal melanomas with monosomy 3 were significantly greater in size than disomy 3 melanoma and showed a significantly greater decrease in thickness at a median of 1.75 years after brachytherapy. The greater decrease in monosomy 3 melanoma thickness after brachytherapy is consistent with other malignancies in which more aggressive pathology has been shown to be associated with a greater initial response to radiotherapy.

  18. Dosimetric and Late Radiation Toxicity Comparison Between Iodine-125 Brachytherapy and Stereotactic Radiation Therapy for Juxtapapillary Choroidal Melanoma

    SciTech Connect

    Krema, Hatem

    2013-07-01

    Purpose: To compare the dose distributions and late radiation toxicities for {sup 125}I brachytherapy (IBT) and stereotactic radiation therapy (SRT) in the treatment of juxtapapillary choroidal melanoma. Methods: Ninety-four consecutive patients with juxtapapillary melanoma were reviewed: 30 have been treated with IBT and 64 with SRT. Iodine-125 brachytherapy cases were modeled with plaque simulator software for dosimetric analysis. The SRT dosimetric data were obtained from the Radionics XKnife RT3 software. Mean doses at predetermined intraocular points were calculated. Kaplan-Meier estimates determined the actuarial rates of late toxicities, and the log–rank test compared the estimates. Results: The median follow-up was 46 months in both cohorts. The 2 cohorts were balanced with respect to pretreatment clinical and tumor characteristics. Comparisons of radiation toxicity rates between the IBT and SRT cohorts yielded actuarial rates at 50 months for cataracts of 62% and 75% (P=.1), for neovascular glaucoma 8% and 47% (P=.002), for radiation retinopathy 59% and 89% (P=.0001), and for radiation papillopathy 39% and 74% (P=.003), respectively. Dosimetric comparisons between the IBT and SRT cohorts yielded mean doses of 12.8 and 14.1 Gy (P=.56) for the lens center, 17.6 and 19.7 Gy (P=.44) for the lens posterior pole, 13.9 and 10.8 Gy (P=.30) for the ciliary body, 61.9 and 69.7 Gy (P=.03) for optic disc center, and 48.9 and 60.1 Gy (P<.0001) for retina at 5-mm distance from tumor margin, respectively. Conclusions: Late radiation-induced toxicities were greater with SRT, which is secondary to the high-dose exposure inherent to the technique as compared with IBT. When technically feasible, IBT is preferred to treat juxtapapillary choroidal melanoma.

  19. Iodine 125 Brachytherapy With Vitrectomy and Silicone Oil in the Treatment of Uveal Melanoma: 1-to-1 Matched Case-Control Series

    SciTech Connect

    McCannel, Tara A. McCannel, Colin A.

    2014-06-01

    Purpose: We initially reported the radiation-attenuating effect of silicone oil 1000 centistokes for iodine 125. The purpose of this report was to compare the clinical outcomes in case patients who had iodine 125 brachytherapy with vitrectomy and silicone oil 1000 centistokes with the outcomes in matched control patients who underwent brachytherapy alone. Methods and Materials: Consecutive patients with uveal melanoma who were treated with iodine 125 plaque brachytherapy and vitrectomy with silicone oil with minimum 1-year follow-up were included. Control patients who underwent brachytherapy alone were matched for tumor size, location, and sex. Baseline patient and tumor characteristics and tumor response to radiation, final visual acuity, macular status, central macular thickness by ocular coherence tomography (OCT), cataract progression, and metastasis at last follow-up visit were compared. Surgical complications were also determined. Results: Twenty case patients met the inclusion criteria. The average follow-up time was 22.1 months in case patients and 19.4 months in control patients. The final logMAR vision was 0.81 in case patients and 1.1 in control patients (P=.071); 8 case patients and 16 control patients had abnormal macular findings (P=.011); and the average central macular thickness by OCT was 293.2 μm in case patients and 408.5 μm in control patients (P=.016). Eleven case patients (55%) and 1 control patient (5%) had required cataract surgery at last follow-up (P=.002). Four patients in the case group and 1 patient in the control group experienced metastasis (P=.18). Among the cases, intraoperative retinal tear occurred in 3 patients; total serous retinal detachment and macular hole developed in 1 case patient each. There was no case of rhegmatogenous retinal detachment, treatment failure, or local tumor dissemination in case patients or control patients. Conclusions: With up to 3 years of clinical follow-up, silicone oil during brachytherapy

  20. Versatile permanent planar implant technique utilizing Iodine-125 seeds imbedded in gelfoam

    SciTech Connect

    Marchese, M.J.; Nori, D.; Anderson, L.L.; Hilaris, B.S.

    1984-05-01

    Tumors attached or adjacent to critical structures can often not be completely resected or resected with adequate surgical margins. Sites involving major blood vessels, the vertebral column or the brain with small residual tumors or suspicious margins often present technical difficulties for standard I-125 or Ir-192 implants. A relatively simple, accurate and inexpensive implant method is decribed using I-125 seeds imbedded in gelfoam to implant permanently into small residual tumors or suspicious margins where standard implant techniques may be unsatisfactory. A method for planning the treatment dose for such an implant is described. Cases involving paraspinal and brain tumors are reported to illustrate the technique.

  1. Radiofrequency ablation and percutaneous permanent iodine-125 implantation as salvage therapy for giant recurrent sclerosing epithelioid fibrosarcoma of the chest wall: A case report

    PubMed Central

    KE, SHAN; DING, XUE-MEI; GAO, JUN; WANG, SHAO-HONG; ZHANG, JUN; KONG, JIAN; SUN, WEN-BING

    2015-01-01

    Sclerosing epithelioid fibrosarcoma (SEF) is a rare soft-tissue sarcoma for which there is no standardized treatment regimen available. The current treatment options for SEF are resection, radiation and chemotherapy. Surgical resection remains the mainstay of therapy for SEF. However, SEF is an aggressive tumor that is prone to repeated local recurrence if not widely excised. Radiation and chemotherapy are less commonly used due to the insensitivity of SEF to these therapies. The treatment of recurrent SEF is even more challenging. The present study describes a patient who presented with a giant recurrent SEF arising from the chest wall that was accompanied by emergent bleeding. The patient was a 70-year-old male who had multiple comorbid diseases, including hypertension and chronic cardiac dysfunction. A computed tomography (CT) scan indicated the involvement of the sternum and anterior mediastinum. However, the patient refused any further surgery. Subsequent to careful discussion and consideration, radiofrequency (RF) ablation and percutaneous iodine-125 implantation was administered. The emergent bleeding was successfully stopped and the tumor was eliminated using RF ablation. Percutaneous iodine-125 implantation under CT guidance established effective control on the growth of the tumor involving the mediastinum. Despite this, the tumor recurred 6 months after treatment. The patient refused any further treatment and was discharged. In conclusion, RF ablation and percutaneous permanent iodine-125 implantation is a feasible and safe salvage therapy for patients with recurrent SEF of the chest wall. PMID:26137032

  2. Long-Term Results of Brachytherapy With Temporary Iodine-125 Seeds in Children With Low-Grade Gliomas

    SciTech Connect

    Korinthenberg, Rudolf; Neuburger, Daniela; Trippel, Michael; Ostertag, Christoph; Nikkhah, Guido

    2011-03-15

    Purpose: To retrospectively review the results of temporary I-125 brachytherapy in 94 children and adolescents with low-grade glioma. Methods and Materials: Treatment was performed in progressive tumors roughly spherical in shape with a diameter of up to 5 cm, including 79 astrocytomas, 5 oligodendrogliomas, 4 oligoastrocytomas, 1 ependymoma, and 5 other tumors. Location was suprasellar/chiasmal in 44, thalamic/basal ganglia in 18, hemispheric in 15, midbrain/pineal region in 13, and lower brainstem in 3. Initially, 8% of patients were free of symptoms, 47% were symptomatic but not disabled, and 30% were slightly, 6% moderately, and 3% severely disabled. Results: 5- and 10-year survival was 97% and 92%. The response to I-125 brachytherapy over the long term was estimated after a median observation period of 38.4 (range, 6.4-171.0) months. At that time, 4 patients were in complete, 27 in partial, and 18 in objective remission; 15 showed stable and 30 progressive tumors. Treatment results did not correlate with age, sex, histology, tumor size, location, or demarcation of the tumor. Secondary treatment became necessary in 36 patients, including 19 who underwent repeated I-125 brachytherapy. At final follow-up, the number of symptom-free patients had risen to 21%. Thirty-eight percent showed symptoms without functional impairment, 19% were slightly and 11% moderately disabled, and only 4% were severely disabled. Conclusions: Response rates similar to those of conventional radiotherapy or chemotherapy can be anticipated with I-125 brachytherapy in tumors of the appropriate size and shape. We believe it to be a useful contribution to the treatment of low-grade gliomas in children.

  3. The Impact of Acute Urinary Retention After Iodine-125 Prostate Brachytherapy on Health-Related Quality of Life

    SciTech Connect

    Roeloffzen, Ellen M.A.; Hinnen, Karel A.; Battermann, Jan J.; Monninkhof, Evelyn M.; Roermund, Joep G.H. van; Gellekom, Marion van; Frank, Steven J.; Vulpen, Marco van

    2010-08-01

    Purpose: To evaluate the impact of acute urinary retention (AUR) in patients treated with {sup 125}I prostate brachytherapy on short- and long-term health-related quality of life (HRQOL); and to assess whether pretreatment HRQOL has additional value in the prediction of AUR. Methods and Materials: For 127 patients treated with {sup 125}I brachytherapy for localized prostate cancer between December 2000 and June 2003, toxicity and HRQOL data were prospectively collected. Patients received a HRQOL questionnaire at five time points: before and 1 month, 6 months, 1 year, and 6 years after treatment. The questionnaire included the RAND-36 generic health survey, the cancer-specific European Organization for Research and Treatment of Cancer core questionnaire (EORTC QLQ-C30), the tumor-specific EORTC prostate cancer module (EORTC QLQ-PR25), and the American Urological Association (AUA) symptom index. Results: Of 127 patients, 13 (10.2%) developed AUR. Patients with AUR had a significantly worse urinary QOL at all time points compared with patients without AUR. The mean difference over time (6 years) between both groups for the EORTC QLQ-PR25 urinary symptom score was 13.0 points (p < 0.001) and for the AUA urinary symptom score was 15.7 points (p = 0.001). Global QOL scores (EORTC QLQ-C30) over time for patients who developed AUR were significantly worse compared with patients without AUR (mean difference 6.7 points; p = 0.043). In multivariate logistic regression analysis, pretreatment International Prostate Symptom Score (p = 0.004) and neoadjuvant hormonal treatment (p = 0.034) were predictors of AUR. Quality of life did not have added predictive value. Conclusion: Acute urinary retention after prostate brachytherapy has a significant negative impact on patient's HRQOL up to 6 years after treatment, in terms of both global QOL measures and urinary symptom scores. Furthermore, our results suggest limited value of pretreatment HRQOL measures for the prediction of AUR.

  4. Novel Parameter Predicting Grade 2 Rectal Bleeding After Iodine-125 Prostate Brachytherapy Combined With External Beam Radiation Therapy

    SciTech Connect

    Shiraishi, Yutaka; Hanada, Takashi; Ohashi, Toshio; Yorozu, Atsunori; Toya, Kazuhito; Saito, Shiro; Shigematsu, Naoyuki

    2013-09-01

    Purpose: To propose a novel parameter predicting rectal bleeding on the basis of generalized equivalent uniform doses (gEUD) after {sup 125}I prostate brachytherapy combined with external beam radiation therapy and to assess the predictive value of this parameter. Methods and Materials: To account for differences among radiation treatment modalities and fractionation schedules, rectal dose–volume histograms (DVHs) of 369 patients with localized prostate cancer undergoing combined therapy retrieved from corresponding treatment planning systems were converted to equivalent dose-based DVHs. The gEUDs for the rectum were calculated from these converted DVHs. The total gEUD (gEUD{sub sum}) was determined by a summation of the brachytherapy and external-beam radiation therapy components. Results: Thirty-eight patients (10.3%) developed grade 2+ rectal bleeding. The grade 2+ rectal bleeding rate increased as the gEUD{sub sum} increased: 2.0% (2 of 102 patients) for <70 Gy, 10.3% (15 of 145 patients) for 70-80 Gy, 15.8% (12 of 76 patients) for 80-90 Gy, and 19.6% (9 of 46 patients) for >90 Gy (P=.002). Multivariate analysis identified age (P=.024) and gEUD{sub sum} (P=.000) as risk factors for grade 2+ rectal bleeding. Conclusions: Our results demonstrate gEUD to be a potential predictive factor for grade 2+ late rectal bleeding after combined therapy for prostate cancer.

  5. [Permanent implant prostate cancer brachytherapy: 2013 state-of-the art].

    PubMed

    Cosset, J-M; Hannoun-Lévi, J-M; Peiffert, D; Delannes, M; Pommier, P; Pierrat, N; Nickers, P; Thomas, L; Chauveinc, L

    2013-04-01

    With an experience of more than 25 years for the pioneers (and more than 14 years in France), permanent implant brachytherapy using iodine 125 seeds (essentially) is now recognized as a valuable alternative therapy for localized low-risk prostate cancer patients. The possible extension of the indications of exclusive brachytherapy towards selected patients in the intermediate-risk group has now been confirmed by several studies. Moreover, for the other patients in the intermediate-risk group and for the patients in the high-risk group, brachytherapy, as an addition to external radiotherapy, could represent one of the best ways to escalate the dose. Different permanent implant brachytherapy techniques have been proposed; preplanning or real-time procedure, loose or stranded seeds (or both), manual or automatic injection of the seeds. The main point here is the ability to perfectly master the procedure and to comply with the dosimetric constraints, which have been recently redefined by the international societies, such as the GEC-ESTRO group. Mid- and long-term results, which are now available in the literature, indicate relapse-free survival rates of about 90% at 5-10 years, the best results being obtained with satisfactory dosimetric data. Comparative data have shown that the incontinence and impotence rates after brachytherapy seemed to be significantly inferior to what is currently observed after surgery. However, a risk of about 3 to 5% of urinary retention is usually reported after brachytherapy, as well as an irritative urinary syndrome, which may significantly alter the quality of life of the patients, and last several months. In spite of those drawbacks, with excellent long-term results, low rates of incontinence and impotence, and emerging new indications (focal brachytherapy, salvage brachytherapy after localized failure of an external irradiation), permanent implant prostate brachytherapy can be expected to be proposed to an increasing number of patients

  6. SU-E-T-55: Biological Equivalent Dose (BED) Comparison Between Permanent Interstitial Brachytherapy and Conventional External Beam Radiotherapy for Prostate Cancer

    SciTech Connect

    Liu, X; Rahimian, J; Cosmatos, H; Goy, B; Heywood, C; Qian, Y

    2014-06-01

    Purpose: The goal of this research is to calculate and compare the Biological Equivalent Dose (BED) between permanent prostate Iodine-125 implant brachytherapy as monotherapy with the BED of conventional external beam radiation therapy (EBRT). Methods: A retrospective study of 605 patients treated with Iodine-125 seed implant was performed in which physician A treated 274 patients and physician B treated 331 patients. All the Brachytherapy treatment plans were created using VariSeed 8 planning system. The Iodine-125 seed source activities and loading patterns varied slightly between the two physicians. The prescription dose is 145 Gy to PTV for each patient. The BED and Tumor Control Probability (TCP) were calculated based on the TG 137 formulas. The BED for conventional EBRT of the prostate given in our institution in 2Gy per fraction for 38 fractions was calculated and compared. Results: Physician A treated 274 patients with an average BED of 123.92±0.87 Gy and an average TCP of 99.20%; Physician B treated 331 patients with an average BED of 124.87±1.12 Gy and an average TCP of 99.30%. There are no statistically significant differences (T-Test) between the BED and TCP values calculated for these two group patients.The BED of the patients undergoing conventional EBRT is calculated to be 126.92Gy. The BED of the patients treated with permanent implant brachytherapy and EBRT are comparable. Our BED and TCP values are higher than the reported values by TG 137 due to higher Iodine-125 seed activity used in our institution. Conclusion: We calculated the BED,a surrogate of the biological response to a permanent prostate brachytherapy using TG 137 formulas and recommendation. The TCP of better than 99% is calculated for these patients. A clinical outcome study of these patients correlating the BED and TCP values with PSA and Gleason Levels as well as patient survival is warranted.

  7. Monte Carlo calculated doses to treatment volumes and organs at risk for permanent implant lung brachytherapy

    NASA Astrophysics Data System (ADS)

    Sutherland, J. G. H.; Furutani, K. M.; Thomson, R. M.

    2013-10-01

    Iodine-125 (125I) and Caesium-131 (131Cs) brachytherapy have been used with sublobar resection to treat stage I non-small cell lung cancer and other radionuclides, 169Yb and 103Pd, are considered for these treatments. This work investigates the dosimetry of permanent implant lung brachytherapy for a range of source energies and various implant sites in the lung. Monte Carlo calculated doses are calculated in a patient CT-derived computational phantom using the EGsnrc user-code BrachyDose. Calculations are performed for 103Pd, 125I, 131Cs seeds and 50 and 100 keV point sources for 17 implant positions. Doses to treatment volumes, ipsilateral lung, aorta, and heart are determined and compared to those determined using the TG-43 approach. Considerable variation with source energy and differences between model-based and TG-43 doses are found for both treatment volumes and organs. Doses to the heart and aorta generally increase with increasing source energy. TG-43 underestimates the dose to the heart and aorta for all implants except those nearest to these organs where the dose is overestimated. Results suggest that model-based dose calculations are crucial for selecting prescription doses, comparing clinical endpoints, and studying radiobiological effects for permanent implant lung brachytherapy.

  8. A permanent breast seed implant as partial breast radiation therapy for early-stage patients: A comparison of palladium-103 and iodine-125 isotopes based on radiation safety considerations

    SciTech Connect

    Keller, Brian; Sankreacha, Raxa; Rakovitch, Eileen; O'Brien, Peter; Pignol, Jean-Philippe . E-mail: Jean-Philippe.Pignol@sw.ca

    2005-06-01

    Purpose: A permanent breast seed implant (PBSI) technique has been developed as a new form of partial adjuvant radiation therapy for early-stage breast cancer. This study compares iodine-125 ({sup 125}I) and palladium-103 ({sup 103}Pd) isotopes by examining the exposure and effective dose (ED) to a patient's partner.Methods and Materials: A low-energy survey meter was used to measure exposure rates as a function of bolus thickness placed over {sup 103}Pd or {sup 125}I seeds. A general mathematical expression for the initial exposure rate at 1 m (x{sub o,1m}) from the skin surface as a function of the implant size, R, and the distance between the skin surface and the implant, d, was derived. Also, a second general equation is proposed to calculate the ED to the patient's partner.Results: The initial exposure rate at 1 meter and the ED are calculated as follows: x{sub o,1m} = (3{alpha})/2R{sup 3}{center_dot}{beta}{sup 3} [e{sup -{beta}}{sup (2R+d)}({beta}R + 1) + e{sup -{beta}}{sup {center_dot}}{sup d}({beta}R - 1)], and ED = aR{sup b} {center_dot} [e{sup -c(2R+d)} {center_dot} (cR + 1) + e{sup -cd} -bar (cR - 1)]. For {sup 125}I, the parameters are: {alpha} = 0.154409, {beta} = 0.388460, a = 197, b = -0.95, and c = 0.38846. For {sup 103}Pd, they are: {alpha} = 0.06877, {beta} = 0.421098, a = 18.6, b -0.78, and c = 0.421098. For implant diameters varying from 2 to 6 cm and skin-to-implant distances varying from 0.7 to 4 cm, the ED is consistently below 2.6 mSv using the {sup 103}Pd isotope, but more than 5 mSv in many instances and possibly up to 20 mSv using {sup 125}I.Conclusions: PBSI using {sup 103}Pd seeds appears safe because the patient's partner ED is consistently below 5 mSv. The{sup 125}I isotope is not recommended for PBSI.

  9. Iodine-125 radiation of posterior uveal melanoma

    SciTech Connect

    Packer, S.

    1987-12-01

    Twenty-eight cases of posterior choroidal melanoma were treated with iodine-125 in gold eye plaques. Eleven cases were located within 3.0 mm of the optic nerve (group A), nine were within 3.0 mm of the fovea (group B), and eight were within 3.0 mm of the optic nerve and fovea (group C). The mean follow-up of group A was 46.3 months; group B, 25.5 months; and group C, 42.7 months. Complications included macular edema, cataract and tumor growth. Visual acuity remained within two lines of that tested preoperatively for 4 of 11 patients in group A, 4 of 9 in group B, and 5 of 8 in group C. These results with iodine-125 suggest it as an appropriate treatment for patients with choroidal melanoma located near optic nerve and/or macula.

  10. Therapeutic implications of iodine-125 cytotoxicity

    SciTech Connect

    Bloomer, W.D.; McLaughlin, W.H.; Adelstein, S.J.

    1982-11-01

    The biological consequences of differential subcellular radionuclide accumulation within nuclear stuctures have important implications for the design and development of new therapeutic agents for cancer management. A growing body of experimental data demonstrates that localization of /sup 125/I within the genome results in marked cytotoxicity. Investigations of iodine-125 labeled iododeoxyuridine, DNA intercalators and tamoxifen are reviewed as representative of this new group of potential radiotherapeutic agents.

  11. Therapeutic implications of iodine-125 cytotoxicity

    SciTech Connect

    Bloomer, W.D.; McLaughlin, W.H.; Adelstein, S.J.

    1982-11-01

    The biological consequences of differential subcellular radionuclide accumulation within nuclear structures have important implications for the design and development of new therapeutic agents for cancer management. A growing body of experimental data demonstrates that localization of /sup 125/I within the genome results in marked cytotoxicity. Investigations of iodine-125 labeled iododeoxyuridine, DNA intercalators and tamoxifen are reviewed as representative of this new group of potential radiotherapeutic agents.

  12. Erectile Function Durability Following Permanent Prostate Brachytherapy

    SciTech Connect

    Taira, Al V.; Merrick, Gregory S.; Galbreath, Robert W.; Butler, Wayne M.; Wallner, Kent E.; Kurko, Brian S.; Anderson, Richard; Lief, Jonathan H.

    2009-11-01

    Purpose: To evaluate long-term changes in erectile function following prostate brachytherapy. Methods and Materials: This study included 226 patients with prostate cancer and preimplant erectile function assessed by the International Index of Erectile Function-6 (IIEF-6) who underwent brachytherapy in two prospective randomized trials between February 2001 and January 2003. Median follow-up was 6.4 years. Pre- and postbrachytherapy potency was defined as IIEF-6 >= 13 without pharmacologic or mechanical support. The relationship among clinical, treatment, and dosimetric parameters and erectile function was examined. Results: The 7-year actuarial rate of potency preservation was 55.6% with median postimplant IIEF of 22 in potent patients. Potent patients were statistically younger (p = 0.014), had a higher preimplant IIEF (p < 0.001), were less likely to be diabetic (p = 0.002), and were more likely to report nocturnal erections (p = 0.008). Potency preservation in men with baseline IIEF scores of 29-30, 24-28, 18-23, and 13-17 were 75.5% vs. 73.6%, 51.7% vs. 44.8%, 48.0% vs. 40.0%, and 23.5% vs. 23.5% in 2004 vs. 2008. In multivariate Cox regression analysis, preimplant IIEF, hypertension, diabetes, prostate size, and brachytherapy dose to proximal penis strongly predicted for potency preservation. Impact of proximal penile dose was most pronounced for men with IIEF of 18-23 and aged 60-69. A significant minority of men who developed postimplant impotence ultimately regained erectile function. Conclusion: Potency preservation and median IIEF scores following brachytherapy are durable. Thoughtful dose sparing of proximal penile structures and early penile rehabilitation may further improve these results.

  13. Brachytherapy

    MedlinePlus

    ... care for brachytherapy catheters. top of page What equipment is used? For permanent implants, radioactive material (which ... the tumor. top of page Who operates the equipment? The equipment is operated by a medical physicist, ...

  14. 76 FR 11526 - In the Matter of Dr. Gary Kao; Order Prohibiting Involvement In NRC-Licensed Activities

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-02

    ... therapeutic purposes. The therapeutic treatments include brachytherapy iodine-125 used for permanent prostate implants. Dr. Kao was an approved authorized user for brachytherapy iodine-125 used for permanent...

  15. Comparison of biochemical failure definitions for permanent prostate brachytherapy

    SciTech Connect

    Kuban, Deborah A. . E-mail: dakuban@mdanderson.org; Levy, Larry B.; Potters, Louis; Beyer, David C.; Blasko, John C.; Moran, Brian J.; Ciezki, Jay P.; Zietman, Anthony L.; Zelefsky, Michael J.; Pisansky, Thomas M.; Elshaikh, Mohamed; Horwitz, Eric M.

    2006-08-01

    Purpose: To assess prostate-specific antigen (PSA) failure definitions for patients with Stage T1-T2 prostate cancer treated by permanent prostate brachytherapy. Methods and Materials: A total of 2,693 patients treated with radioisotopic implant as solitary treatment for T1-T2 prostatic adenocarcinoma were studied. All patients had a pretreatment PSA, were treated at least 5 years before analysis, 1988 to 1998, and did not receive hormonal therapy before recurrence. Multiple PSA failure definitions were tested for their ability to predict clinical failure. Results: Definitions which determined failure by a certain increment of PSA rise above the lowest PSA level to date (nadir + x ng/mL) were more sensitive and specific than failure definitions based on PSA doubling time or a certain number of PSA rises. The sensitivity and specificity for the nadir + 2 definition were 72% and 83%, vs. 51% and 81% for 3 PSA rises. The surgical type definitions (PSA exceeding an absolute value) could match this sensitivity and specificity but only when failure was defined as exceeding a PSA level in the 1-3 ng/mL range and only when patients were allowed adequate time to nadir. When failure definitions were compared by time varying covariate regression analysis, nadir + 2 ng/mL retained the best fit. Conclusions: For patients treated by permanent radioisotopic implant for prostate cancer, the definition nadir + 2 ng/mL provides the best surrogate for failure throughout the entire follow-up period, similar to patients treated by external beam radiotherapy. Therefore, the same PSA failure definition could be used for both modalities. For brachytherapy patients with long-term follow-up, at least 6 years, defining failure as exceeding an absolute PSA level in the 0.5 ng/mL range may be reasonable.

  16. Primary Causes of Death After Permanent Prostate Brachytherapy

    SciTech Connect

    Bittner, Nathan; Merrick, Gregory S. Galbreath, Robert W.; Butler, Wayne M.; Wallner, Kent E.; Allen, Zachariah A.; Brammer, Sarah G.; Moyad, Mark

    2008-10-01

    Purpose: To evaluate the primary causes of death in low-risk (low-risk), intermediate-risk (intermediate-risk), and high-risk (high-risk) patients undergoing permanent prostate brachytherapy with or without supplemental therapies. Methods and Materials: From April 1995 through November 2004, a total of 1,354 consecutive patients underwent prostate brachytherapy. All patients underwent brachytherapy >3 years before analysis. Of the patients, 532 (39.3%) received androgen deprivation therapy and 703 (51.9%) received supplemental radiation therapy. The median follow-up was 5.4 years. Multiple parameters were evaluated as predictors of cause-specific, biochemical progression-free, and overall survival. Results: The 10-year cause-specific survival was 97.0% (99.7%, 99.0%, and 90.1% for low-risk, intermediate-risk, and high-risk patients). Overall survival was 76.7% (82.5%, 78.3%, and 67.6% for low-, intermediate-, and high-risk patients, respectively). The cumulative death rate for cardiovascular disease was 11.5% (8.7%, 9.3%, and 19.8% for low-, intermediate-, and high-risk patients). The death rate from second malignancies (nonprostate cancer) was 7.2% and was not substantially different when stratified by risk group. Death from all other causes was 6.5% for the entire cohort but 1.3%, 5.0%, and 10.8% for low-, intermediate-, and high-risk patients. In multivariate analysis, death from prostate cancer was best predicted by Gleason score and risk group, whereas death from cardiovascular disease, nonprostate cancer, and all other causes were most closely related to patient age and tobacco use. Conclusions: Although cardiovascular mortality was the predominant cause of death, prostate cancer was responsible for approximately 10% of all deaths. In particular, overall survival was poorest in the high-risk group. Although high-risk patients were most likely to die of prostate cancer, the divergence in overall survival between high-risk and lower-risk patients primarily

  17. Segmental Urethral Dosimetry and Urinary Toxicity in Patients With No Urinary Symptoms Before Permanent Prostate Brachytherapy

    SciTech Connect

    Thomas, Carys; Keyes, Mira Liu, Mitchell; Moravan, Veronika

    2008-10-01

    Purpose: To determine whether segmental urethral dosimetry is predictive for the degree of urinary morbidity after prostate brachytherapy in patients with no urinary symptoms before prostate brachytherapy. Methods and Materials: Between May 2000 and November 2005, 1,107 patients underwent iodine-125 monotherapy with urethral sparing techniques. A total of 166 patients fulfilled the selection criteria: baseline (International Prostate Symptom Score) IPSS {<=}5, no androgen deprivation therapy, and prostate ultrasound planning volumes (PUTV) <45 mL. The median follow-up was 44 months. Urinary morbidity was defined by maximum increase in IPSS, time to IPSS resolution, maximum Radiation Therapy Oncology Group (RTOG) score, time to RTOG resolution, and urinary retention. Surrogate deviated urethra was contoured and doses calculated at the base, mid-prostate, apex, and urogenital diaphragm. Univariate and multivariate analysis was used to evaluate urethral and prostate dosimetry, age, PUTV, and number of needles for their association with urinary morbidity. Results: Urethral dose was fairly constant in all urethra segments except prostate base, where the variation in does was large. On multivariate analysis, higher urethral base D50, V100, and larger PUTV were predictive for higher maximum increase in IPSS. Higher urethral base V100 and larger PUTV predicted for prolonged IPSS resolution. Higher urethral base D50 and larger needle number predicted for longer RTOG resolution. Higher urethral base V100 predicted for RTOG {>=}2 toxicity. Conclusions: Radiation dose to the urethral base, larger PUTV, and needle number, predicted for increased urinary toxicity after prostate brachytherapy. Correlation between urinary morbidity and urethral base dosimetry may reflect a large variation in urethral dose observed at the prostate base.

  18. Long-Term Results of an RTOG Phase II Trial (00-19) of External-Beam Radiation Therapy Combined With Permanent Source Brachytherapy for Intermediate-Risk Clinically Localized Adenocarcinoma of the Prostate

    SciTech Connect

    Lawton, Colleen A.; Yan, Yan; Lee, W. Robert; Gillin, Michael; Firat, Selim; Baikadi, Madhava; Crook, Juanita; Kuettel, Michael; Morton, Gerald; Sandler, Howard

    2012-04-01

    Purpose: External-beam radiation therapy combined with low-doserate permanent brachytherapy are commonly used to treat men with localized prostate cancer. This Phase II trial was performed to document late gastrointestinal or genitourinary toxicity as well as biochemical control for this treatment in a multi-institutional cooperative group setting. This report defines the long-term results of this trial. Methods and Materials: All eligible patients received external-beam radiation (45 Gy in 25 fractions) followed 2-6 weeks later by a permanent iodine 125 implant of 108 Gy. Late toxicity was defined by the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer late radiation morbidity scoring scheme. Biochemical control was defined by the American Society for Therapeutic Radiology and Oncology (ASTRO) Consensus definition and the ASTRO Phoenix definition. Results: One hundred thirty-eight patients were enrolled from 20 institutions, and 131 were eligible. Median follow-up (living patients) was 8.2 years (range, 2.7-9.3 years). The 8-year estimate of late grade >3 genitourinary and/or gastrointestinal toxicity was 15%. The most common grade >3 toxicities were urinary frequency, dysuria, and proctitis. There were two grade 4 toxicities, both bladder necrosis, and no grade 5 toxicities. In addition, 42% of patients complained of grade 3 impotence (no erections) at 8 years. The 8-year estimate of biochemical failure was 18% and 21% by the Phoenix and ASTRO consensus definitions, respectively. Conclusion: Biochemical control for this treatment seems durable with 8 years of follow-up and is similar to high-dose external beam radiation alone or brachytherapy alone. Late toxicity in this multi-institutional trial is higher than reports from similar cohorts of patients treated with high-dose external-beam radiation alone or permanent low-doserate brachytherapy alone, perhaps suggesting further attention to strategies that limit doses to

  19. Urethral toxicity after LDR brachytherapy: experience in Japan.

    PubMed

    Tanaka, Nobumichi; Asakawa, Isao; Hasegawa, Masatoshi; Fujimoto, Kiyohide

    2015-01-01

    Urinary toxicity is common after low-dose-rate (LDR) brachytherapy, and the resolution of urinary toxicity is a concern. In particular, urinary frequency is the most common adverse event among the urinary toxicities. We have previously reported that approximately 70% of patients experience urinary frequency during the first 6 months after seed implantation. Most urinary adverse events were classified as Grade 1, and Grade 2 or higher adverse events were rare. The incidence of urinary retention was approximately 2-4%. A high International Prostate Symptom Score before seed implantation was an independent predictor of acute urinary toxicity of Grade 2 or higher. Several previous reports from the United States also supported this trend. In Japan, LDR brachytherapy was legally approved in 2003. A nationwide prospective cohort study entitled Japanese Prostate Cancer Outcome Study of Permanent Iodine-125 Seed Implantation was initiated in July 2005. It is an important issue to limit urinary toxicities in patients who undergo LDR brachytherapy.

  20. Relationship between two year PSA nadir and biochemical recurrence in prostate cancer patients treated with iodine-125 brachytherap*

    PubMed Central

    Franca, Carlos Antônio da Silva; Vieira, Sérgio Lannes; Carvalho, Antonio Carlos Pires; Bernabe, Antonio Jose Serrano; Penna, Antonio Belmiro Rodrigues Campbell

    2014-01-01

    Objective To evaluate the relationship between two year PSA nadir (PSAn) after brachytherapy and biochemical recurrence rates in prostate cancer patients. Materials and Methods In the period from January 1998 to August 2007, 120 patients were treated with iodine-125 brachytherapy alone. The results analysis was based on the definition of biochemical recurrence according to the Phoenix Consensus. Results Biochemical control was observed in 86 patients (71.7%), and biochemical recurrence, in 34 (28.3%). Mean PSAn was 0.53 ng/ml. The mean follow-up was 98 months. The patients were divided into two groups: group 1, with two year PSAn < 0.5 ng/ml after brachytherapy (74 patients; 61.7%), and group 2, with two year PSAn ≥ 0.5 ng/ml after brachytherapy (46 patients; 38.3%). Group 1 presented biochemical recurrence in 15 patients (20.3%), and group 2, in 19 patients (43.2%) (p < 0.02). The analysis of biochemical disease-free survival at seven years, stratified by the two groups, showed values of 80% and 64% (p < 0.02), respectively. Conclusion Levels of two year PSAn ≥ 0.5 ng/ml after brachytherapy are strongly correlated with a poor prognosis. This fact may help to identify patients at risk for disease recurrence. PMID:25741055

  1. Interstitial iodine-125 implant in the management of unresectable pancreatic carcinoma

    SciTech Connect

    Syed, A.M.; Puthawala, A.A.; Neblett, D.L.

    1983-09-01

    Eighteen patients with locally advanced adenocarcinoma of the head, body and tail of the pancreas were treated by a combination of biliary bypass, external and interstitial irradiation at Southern California Cancer Center of California Hospital Medical Center, Los Angeles, and Memorial Hospital Medical Center of Long Beach, Long Beach, CA, from July 31, 1975 to December 31, 1980. A dose of 3000 to 5000 rad was delivered to the pancreas and regional lymph nodes by external irradiation utilizing megavoltage units and 10,000 to 15,000 rad to the pancreas and metastatic lymph nodes by permanent Iodine-125 implants. In this group of 18 patients with unresectable carcinoma of the pancreas, excellent palliation of pain, jaundice and vomiting was achieved, with a median survival of 14 months.

  2. Determination of the prescription dose for biradionuclide permanent prostate brachytherapy

    SciTech Connect

    Nuttens, V. E.; Lucas, S.

    2008-12-15

    A model based on the linear quadratic model that has been corrected for repopulation, sublethal cell damage repair, and RBE effect has been used to determine the prescription dose for prostate permanent brachytherapy using seeds loaded with a mixture of {sup 103}Pd and {sup 125}I or a mixture of {sup 103}Pd and {sup 131}Cs. The prescription dose was determined by comparing the tumor cell survival fractions between the considered biradionuclide seed implant and one monoradionuclide seed implant chosen from {sup 103}Pd, {sup 125}I, and {sup 131}Cs. Prostate edema is included in the model. The influence of the value of the radiobiological parameters and RBE were also investigated. Two mixtures of radionuclides were considered: {sup 103}Pd{sub 0.75}-{sup 125}I{sub 0.25} and {sup 103}Pd{sub 0.25}-{sup 131}Cs{sub 0.75}, where the subscripts indicate the fractions of total initial internal activity in the biradionuclide seed. These fractions were selected in order to obtain a dose distribution that lies between that of {sup 103}Pd and {sup 125}I/{sup 131}Cs. As expected, the computed prescription dose values are dependent on the model parameters (edema half-life and magnitude, radiobiogical parameters, and RBE). The radionuclide used as a benchmark also has a strong impact on the derived prescribed dose. The large uncertainties in the radiobiological parameters and RBE values produce big errors in the computed prescribed dose. Averaged over the range of all the parameters and depending on the radionuclide used as a benchmark (in subscript), the derived prescription dose for the first mixture (PdI) would be: D{sub Pd}{sup PdI}=142{sub -16}{sup +15} Gy and D{sub I}{sup PdI}=142{sub -8}{sup +6} Gy; and D{sub Pd}{sup PdCs}=128{sub -13}{sup +13} Gy and D{sub Cs}{sup PdCs}=115{sub -7}{sup +6} Gy for the PdCs mixture. The uncertainties could be reduced if the radiobiological parameters and RBE value were known more accurately. However, as edema characteristics are patient

  3. Primary Gleason Grade 4 Impact on Biochemical Recurrence After Permanent Interstitial Brachytherapy in Japanese Patients With Low- or Intermediate-Risk Prostate Cancer

    SciTech Connect

    Uesugi, Tatsuya; Saika, Takashi; Edamura, Kohei; Nose, Hiroyuki; Kobuke, Makoto; Ebara, Shin; Abarzua, Fernand; Katayama, Norihisa; Yanai, Hiroyuki; Nasu, Yasutomo; Kumon, Hiromi

    2012-02-01

    Purpose: To reveal a predictive factor for biochemical recurrence (BCR) after permanent prostate brachytherapy (PPB) using iodine-125 seed implantation in patients with localized prostate cancer classified as low or intermediate risk based on National Comprehensive Cancer Network (NCCN) guidelines. Methods and Materials: From January 2004 to December 2009, 414 consecutive Japanese patients with clinically localized prostate cancer classified as low or intermediate risk based on the NCCN guidelines were treated with PPB. The clinical factors including pathological data reviewed by a central pathologist and follow-up data were prospectively collected. Kaplan-Meier and Cox regression analyses were used to assess the factors associated with BCR. Results: Median follow-up was 36.5 months. The 2-, 3-, 4-, and 5-year BCR-free rates using the Phoenix definition were 98.3%, 96.0%, 91.6%, and 87.0%, respectively. On univariate analysis, the Gleason score, especially primary Gleason grade 4 in biopsy specimens, was a strong predicting factor (p < 0.0001), while age, initial prostate-specific antigen (PSA) level, T stage, and minimal dose delivered to 90% of the prostate volume (D90) were insignificant. Multivariate analysis indicated that a primary Gleason grade 4 was the most powerful prognostic factor associated with BCR (hazard ratio = 6.576, 95% confidence interval, 2.597-16.468, p < 0.0001). Conclusions: A primary Gleason grade 4 carried a worse BCR prognosis than the primary grade 3 in patients treated with PPB. Therefore, the indication for PPB in patients with a Gleason sum of 4 + 3 deserves careful and thoughtful consideration.

  4. 78 FR 41125 - Interim Enforcement Policy for Permanent Implant Brachytherapy Medical Event Reporting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-09

    ... COMMISSION Interim Enforcement Policy for Permanent Implant Brachytherapy Medical Event Reporting AGENCY... discretion for certain violations of regulations for reporting medical events occurring under an NRC licensee...: Background In SECY-05-0234, ``Adequacy of Medical Event Definitions in 10 CFR 35.3045, and...

  5. Alternative Dose for Choroidal Melanoma Treated With an Iodine-125 Radioactive Plaque: A Single-Institution Retrospective Study

    SciTech Connect

    Saconn, Paul A.; Gee, Christopher J.; Greven, Craig M.; McCoy, Thomas P.; Ekstrand, Kenneth E.; Greven, Kathryn M.

    2010-11-01

    Purpose: The Collaborative Ocular Melanoma Study (COMS) established iodine-125 plaque brachytherapy as an accepted standard treatment for medium-size choroidal melanoma. In the COMS, the prescription dose was 85 Gy. This is a retrospective review of our outcomes in patients treated with lower doses than those used in the COMS. Methods and Materials: From 1990 to 2004, 62 patients were treated with iodine-125 plaque brachytherapy for choroidal melanoma. COMS eye plaques were used with dose prescribed to the apex of the tumor. The median and average dose rates at the tumor apex were 63.5 cGy/h and 62.7 cGy/h, respectively. The median and average total doses were 63.0 Gy and 62.5 Gy (range, 56-69 Gy), respectively. The median and mean durations of implant were 100.0 hours and 101.1 hours (range, 71-165 hours). Results: Median follow-up time was 58.2 months. The 5-year outcomes including overall survival, disease-free survival, cause-specific survival, local failure, secondary enucleation rate, and visual acuity (VA) <20/200 were estimated using the Kaplan-Meier method. Overall, there were 7 local failures, 4 distant failures, and 10 secondary enucleations (6 due to local failure and 4 due to treatment complications). Univariate analysis was performed to identify significant prognostic factors associated with disease-free survival (baseline VA in tumor eye, tumor shape), cause-specific survival (diabetic retinopathy), local failure (none found), secondary enucleation rate (diabetic retinopathy, basal tumor dimension) and VA <20/200 (diabetic retinopathy, tumor shape, age, retinal detachment, treatment depth, and history of vision-limiting condition). Conclusions: Our survival and local control outcomes are comparable to those of the COMS. However, VA at 5 years seems to be better. Lower doses of radiation could potentially lead to better visual outcomes.

  6. Iodine-125 Seeds Strand for Treatment of Tumor Thrombus in Inferior Vena Cava: An Experimental Study in a Rabbit Model

    SciTech Connect

    Zhang, Wen Yan, Zhiping Luo, Jianjun Fang, Zhuting Wu, Linlin Liu, QingXin Qu, Xudong Liu, Lingxiao Wang, Jianhua

    2013-10-15

    Objective: The purpose of this study was to establish an animal model of implanted inferior vena cava tumor thrombus (IVCTT) and to evaluate the effect of linear iodine-125 seeds strand in treating implanted IVCTT. Methods: Tumor cell line VX{sub 2} was inoculated subcutaneously into New Zealand rabbit to develop the parent tumor. The tumor strip was inoculated into inferior vena cava (IVC) to establish the IVCTT model. The IVCTT was confirmed by multidetector computed tomography (MDCT) after 2 weeks. Twelve rabbits with IVCTT were randomly divided into two groups. Treatment group (group T; n = 6) underwent Iodine-125 seeds brachytherapy, and the control group (group C; n = 6) underwent blank seeds strand. The blood laboratory examination (including blood routine examination, hepatic and renal function), body weight, survival time, and IVCTT volume by MDCT were monitored. All rabbits were dissected postmortem, and the therapeutic effects were evaluated on the basis of histopathology. The proliferating cell nuclear antigen index (PI) and apoptosis index (AI) of IVCTT were compared between two groups. T test, Wilcoxon rank test, and Kaplan-Meier survival curve analysis were used. Results: The success rate of establishing IVCTT was 100 %. The body weight loss and cachexia of rabbits in group C appeared earlier than in group T. Body weight in the third week, the mean survival time, PI, AI in groups T and C were 2.23 {+-} 0.12 kg, 57.83 {+-} 8.68 days, (16.73 {+-} 5.18 %), (29.47 {+-} 7.18 %), and 2.03 {+-} 0.13 kg, 43.67 {+-} 5.28 days, (63.01 {+-} 2.01 %), (6.02 {+-} 2.93 %), respectively. There were statistically significant differences between group T and group C (P < 0.05). The IVCTT volume of group T was remarkably smaller than that of group C. Conclusions: Injecting and suspensory fixing VX2 tumor strip into IVC is a reliable method to establish IVCTT animal model. The linear Iodine-125 seeds strand brachytherapy was a safe and effective method for treating IVCTT

  7. Ejaculatory Function After Permanent {sup 125}I Prostate Brachytherapy for Localized Prostate Cancer

    SciTech Connect

    Huyghe, Eric Delannes, Martine; Wagner, Fabien M.; Delaunay, Boris; Nohra, Joe; Thoulouzan, Matthieu; Shut-Yee, J. Yeung; Plante, Pierre; Soulie, Michel; Thonneau, Patrick; Bachaud, Jean Marc

    2009-05-01

    Purpose: Ejaculatory function is an underreported aspect of male sexuality in men treated for prostate cancer. We conducted the first detailed analysis of ejaculatory function in patients treated with permanent {sup 125}I prostate brachytherapy for localized prostate cancer. Patients and Methods: Of 270 sexually active men with localized prostate cancer treated with permanent {sup 125}I prostate brachytherapy, 241 (89%), with a mean age of 65 years (range, 43-80), responded to a mailed questionnaire derived from the Male Sexual Health Questionnaire regarding ejaculatory function. Five aspects of ejaculatory function were examined: frequency, volume, dry ejaculation, pleasure, and pain. Results: Of the 241 sexually active men, 81.3% had conserved ejaculatory function after prostate brachytherapy; however, the number of patients with rare/absent ejaculatory function was double the pretreatment number (p < .0001). The latter finding was correlated with age (p < .001) and the preimplant International Index of Erectile Function score (p < .001). However, 84.9% of patients with maintained ejaculatory function after implantation reported a reduced volume of ejaculate compared with 26.9% before (p < .001), with dry ejaculation accounting for 18.7% of these cases. After treatment, 30.3% of the patients experienced painful ejaculation compared with 12.9% before (p = .0001), and this was associated with a greater number of implanted needles (p = .021) and the existence of painful ejaculation before implantation (p < .0001). After implantation, 10% of patients who continued to be sexually active experienced no orgasm compared with only 1% before treatment. in addition, more patients experienced late/difficult or weak orgasms (p = .001). Conclusion: Most men treated with brachytherapy have conserved ejaculatory function after prostate brachytherapy. However, most of these men experience a reduction in volume and a deterioration in orgasm.

  8. SU-E-T-259: Particle Swarm Optimization in Radial Dose Function Fitting for a Novel Iodine-125 Seed

    SciTech Connect

    Wu, X; Duan, J; Popple, R; Huang, M; Shen, S; Brezovich, I; Cardan, R; Benhabib, S

    2014-06-01

    Purpose: To determine the coefficients of bi- and tri-exponential functions for the best fit of radial dose functions of the new iodine brachytherapy source: Iodine-125 Seed AgX-100. Methods: The particle swarm optimization (PSO) method was used to search for the coefficients of the biand tri-exponential functions that yield the best fit to data published for a few selected radial distances from the source. The coefficients were encoded into particles, and these particles move through the search space by following their local and global best-known positions. In each generation, particles were evaluated through their fitness function and their positions were changed through their velocities. This procedure was repeated until the convergence criterion was met or the maximum generation was reached. All best particles were found in less than 1,500 generations. Results: For the I-125 seed AgX-100 considered as a point source, the maximum deviation from the published data is less than 2.9% for bi-exponential fitting function and 0.2% for tri-exponential fitting function. For its line source, the maximum deviation is less than 1.1% for bi-exponential fitting function and 0.08% for tri-exponential fitting function. Conclusion: PSO is a powerful method in searching coefficients for bi-exponential and tri-exponential fitting functions. The bi- and tri-exponential models of Iodine-125 seed AgX-100 point and line sources obtained with PSO optimization provide accurate analytical forms of the radial dose function. The tri-exponential fitting function is more accurate than the bi-exponential function.

  9. [Brachytherapy].

    PubMed

    Itami, Jun

    2014-12-01

    Brachytherapy do require a minimal expansion of CTV to obtain PTV and it is called as ultimate high precision radiation therapy. In high-dose rate brachytherapy, applicators will be placed around or into the tumor and CT or MRI will be performed with the applicators in situ. With such image-guided brachytherapy (IGBT) 3-dimensional treatment planning becomes possible and DVH of the tumor and organs at risk can be obtained. It is now even possible to make forward planning satisfying dose constraints. Traditional subjective evaluation of brachytherapy can be improved to the objective one by IGBT. Brachytherapy of the prostate cancer, cervical cancer, and breast cancer with IGBT technique was described.

  10. Long-Term Outcome for Clinically Localized Prostate Cancer Treated With Permanent Interstitial Brachytherapy

    SciTech Connect

    Taira, Al V.; Merrick, Gregory S.; Butler, Wayne M.; Galbreath, Robert W.; Lief, Jonathan; Adamovich, Edward; Wallner, Kent E.

    2011-04-01

    Purpose: To present the largest series of prostate cancer brachytherapy patients treated with modern brachytherapy techniques and postimplant day 0 dosimetric evaluation. Methods and Materials: Between April 1995 and July 2006, 1,656 consecutive patients were treated with permanent interstitial brachytherapy. Risk group stratification was carried out according to the Mt. Sinai guidelines. Median follow-up was 7.0 years. The median day 0 minimum dose covering at least 90% of the target volume was 118.8% of the prescription dose. Cause of death was determined for each deceased patient. Multiple clinical, treatment, and dosimetric parameters were evaluated for impact on the evaluated survival parameters. Results: At 12 years, biochemical progression-free survival (bPFS), cause-specific survival (CSS), and overall survival (OS) for the entire cohort was 95.6%, 98.2%, and 72.6%, respectively. For low-, intermediate-, and high-risk patients, bPFS was 98.6%, 96.5%, and 90.5%; CSS was 99.8%, 99.3%, and 95.2%; and OS was 77.5%, 71.1%, and 69.2%, respectively. For biochemically controlled patients, the median posttreatment prostate-specific antigen (PSA) concentration was 0.02 ng/ml. bPFS was most closely related to percent positive biopsy specimens and risk group, while Gleason score was the strongest predictor of CSS. OS was best predicted by patient age, hypertension, diabetes, and tobacco use. At 12 years, biochemical failure and cause-specific mortality were 1.8% and 0.2%, 5.1% and 2.1%, and 10.4% and 7.1% for Gleason scores 5 to 6 and 7 and {>=}8, respectively. Conclusions: Excellent long-term outcomes are achievable with high-quality brachytherapy for low-, intermediate-, and high-risk patients. These results compare favorably to alternative treatment modalities including radical prostatectomy.

  11. Brachytherapy

    MedlinePlus

    ... Who will be involved in this procedure? The delivery of brachytherapy requires a treatment team, including a ... are specially trained technologists who may assist in delivery of the treatments. The radiation therapy nurse provides ...

  12. Rectal-wall dose dependence on postplan timing after permanent-seed prostate brachytherapy

    SciTech Connect

    Taussky, Daniel; Yeung, Ivan; Williams, Theresa; Pearson, Shannon; McLean, Michael; Pond, Gregory; Crook, Juanita . E-mail: Juanita.crook@rmp.uhn.on.ca

    2006-06-01

    Purpose: Dose to rectal wall after permanent-seed prostate brachytherapy is dependent on distance between posterior prostatic seeds and anterior rectal wall and is influenced by postimplant periprostatic edema. We analyzed the effect of postplan timing on anterior rectal-wall dose. Methods and Materials: Twenty patients received permanent seed {sup 125}I brachytherapy as monotherapy (145 Gy). Implants were preplanned by use of transrectal ultrasound (TRUS) and carried out by use of preloaded needles. Postimplant dosimetry was calculated by use of magnetic resonance imaging-computed tomography fusion on Days 1, 8, and 30. The anterior rectal-wall dose is reported as the isodose enclosing 1.0 or 2.0 cc of rectal wall and as the RV100 in cc. Results: The dose to rectal wall increased progressively over time. The median increase in dose to 1.0 cc of rectal wall (RD [1 cc]) from Day 1 to 30 was 39.2 Gy (p < 0.001). RV100 increased from a median of 0.07 cc on Day 1 to 0.67 cc on Day 30. The most significant predictor of rectal-wall dose (RD [1 cc], RD [2 cc], or RV100) was the time of evaluation (p < 0.001). Conclusion: Although periprostatic edema cannot be quantified by postimplant imaging, the dose to the anterior rectal wall increases significantly over time as prostatic and periprostatic edema resolve. Critical-organ dose reporting and guidelines for minimizing toxicity must take into account the time of the assessment.

  13. Analysis of the Contribution of Charge Transport in Iodine-125 induced DNA Damage

    PubMed Central

    Ndlebe, Thabisile; Panyutin, Igor; Neumann, Ronald

    2009-01-01

    Auger electron emitters, like iodine-125, are the radionuclides of choice for gene-targeted radiotherapy. The highly localized damage they induced in DNA is produced by three mechanisms: direct damage by the emitted Auger electrons, indirect damage by diffusible free radicals produced by Auger electrons travelling in water, and charge neutralization of the residual, highly positively charged, tellurium daughter atom by stripping electrons from covalent bonds of neighboring residues. The purpose of our work was to determine whether these mechanisms proceed through an intermediate energy transfer step along DNA. It was proposed that this intermediate step proceeds through the charge transport mechanism in DNA. Conventional charge transport has been described as either a hopping mechanism initiated by charge injection into DNA and propagated by charge migration along the DNA, or a tunneling mechanism in which charge moves directly from a donor to an acceptor within DNA. Well-known barriers for the hopping mechanism were used to probe the role of charge transport in 125I induced DNA damage. We studied their effect on the distribution of DNA breaks produced by the decay of iodine-125 in samples frozen at −80°C. We found that these barriers had no measurable effect on the iodine-125 breaks distribution. PMID:20041764

  14. Iodine-125 radiolabeling of silver nanoparticles for in vivo SPECT imaging

    PubMed Central

    Chrastina, Adrian; Schnitzer, Jan E

    2010-01-01

    Silver nanoparticles are increasingly finding applications in medicine; however, little is known about their in vivo tissue distribution. Here, we have developed a rapid method for radiolabeling of silver nanoparticles with iodine-125 in order to track in vivo tissue uptake of silver nanoparticles after systemic administration by biodistribution analysis and single-photon emission computerized tomography (SPECT) imaging. Poly(N-vinyl-2 -pyrrolidone)-capped silver nanoparticles with an average size of 12 nm were labeled by chemisorption of iodine-125 with a > 80% yield of radiolabeling efficiency. Radiolabeled silver nanoparticles were intravenously injected in Balb/c mice, and the in vivo distribution pattern of these nanoparticles was evaluated by noninvasive whole-body SPECT imaging, which revealed uptake of the nanoparticles in the liver and spleen. Biodistribution analysis confirmed predominant accumulation of the silver nanoparticles in the spleen (41.5%ID/g) and liver (24.5%ID/g) at 24 h. Extensive uptake in the tissues of the reticuloendothelial system suggests that further investigation of silver nanoparticle interaction with hepatic and splenic tissues at the cellular level is critical for evaluation of the in vivo effects and potential toxicity of silver nanoparticles. This method enables rapid iodine-125 radiolabeling of silver nanoparticles with a specific activity sufficient for in vivo imaging and biodistribution analysis. PMID:20856841

  15. Dose escalation in permanent brachytherapy for prostate cancer: dosimetric and biological considerations

    NASA Astrophysics Data System (ADS)

    Li, X. Allen; Wang, Jian Z.; Stewart, Robert D.; Di Biase, Steven J.

    2003-09-01

    No prospective dose escalation study for prostate brachytherapy (PB) with permanent implants has been reported. In this work, we have performed a dosimetric and biological analysis to explore the implications of dose escalation in PB using 125I and 103Pd implants. The concept of equivalent uniform dose (EUD), proposed originally for external-beam radiotherapy (EBRT), is applied to low dose rate brachytherapy. For a given 125I or 103Pd PB, the EUD for tumour that corresponds to a dose distribution delivered by EBRT is calculated based on the linear quadratic model. The EUD calculation is based on the dose volume histogram (DVH) obtained retrospectively from representative actual patient data. Tumour control probabilities (TCPs) are also determined in order to compare the relative effectiveness of different dose levels. The EUD for normal tissue is computed using the Lyman model. A commercial inverse treatment planning algorithm is used to investigate the feasibility of escalating the dose to prostate with acceptable dose increases in the rectum and urethra. The dosimetric calculation is performed for five representative patients with different prostate sizes. A series of PB dose levels are considered for each patient using 125I and 103Pd seeds. It is found that the PB prescribed doses (minimum peripheral dose) that give an equivalent EBRT dose of 64.8, 70.2, 75.6 and 81 Gy with a fraction size of 1.8 Gy are 129, 139, 150 and 161 Gy for 125I and 103, 112, 122 and 132 Gy for 103Pd implants, respectively. Estimates of the EUD and TCP for a series of possible prescribed dose levels (e.g., 145, 160, 170 and 180 Gy for 125I and 125, 135, 145 and 155 for 103Pd implants) are tabulated. The EUD calculation was found to depend strongly on DVHs and radiobiological parameters. The dosimetric calculations suggest that the dose to prostate can be escalated without a substantial increase in both rectal and urethral dose. For example, increasing the PB prescribed dose from 145 to

  16. American Society for Radiation Oncology (ASTRO) and American College of Radiology (ACR) practice guideline for the transperineal permanent brachytherapy of prostate cancer.

    PubMed

    Rosenthal, Seth A; Bittner, Nathan H J; Beyer, David C; Demanes, D Jeffrey; Goldsmith, Brian J; Horwitz, Eric M; Ibbott, Geoffrey S; Lee, W Robert; Nag, Subir; Suh, W Warren; Potters, Louis

    2011-02-01

    Transperineal permanent prostate brachytherapy is a safe and efficacious treatment option for patients with organ-confined prostate cancer. Careful adherence to established brachytherapy standards has been shown to improve the likelihood of procedural success and reduce the incidence of treatment-related morbidity. A collaborative effort of the American College of Radiology (ACR) and American Society for Therapeutic Radiation Oncology (ASTRO) has produced a practice guideline for permanent prostate brachytherapy. The guideline defines the qualifications and responsibilities of all the involved personnel, including the radiation oncologist, physicist and dosimetrist. Factors with respect to patient selection and appropriate use of supplemental treatment modalities such as external beam radiation and androgen suppression therapy are discussed. Logistics with respect to the brachytherapy implant procedure, the importance of dosimetric parameters, and attention to radiation safety procedures and documentation are presented. Adherence to these practice guidelines can be part of ensuring quality and safety in a successful prostate brachytherapy program.

  17. Inverse planning optimization for hybrid prostate permanent-seed implant brachytherapy plans using two source strengths.

    PubMed

    Cunha, J Adam M; Pickett, Barby; Pouliot, Jean

    2010-06-03

    The purpose is to demonstrate the ability to generate clinically acceptable prostate permanent seed implant plans using two seed types which are identical except for their activity. The IPSA inverse planning algorithms were modified to include multiple dose matrices for the calculation of dose from different sources, and a selection algorithm was implemented to allow for the swapping of source type at any given source position. Five previously treated patients with a range of prostate volumes from 20-48 cm3 were re-optimized under two hybrid scenarios: (1) using 0.32 and 0.51 mGy m2 / h 125I, and (2) using 0.64 and 0.76 mGy m2 / h 125I. Isodose lines were generated and dosimetric indices , V150Prostate, D90Prostate, V150Urethra, V125Urethra, V120Urethra,V100Urethra, and D10Urethra were calculated. The algorithm allows for the generation of single-isotope, multi-activity hybrid brachytherapy plans. By dealing with only one radionuclide, but of different activity, the biology is unchanged from a standard plan. All V100Prostate were within 2.3 percentage points for every plan and always above the clinically desirable 95%. All V150Urethra were identically zero, and V120Urethra is always below the clinically acceptable value of 1.0 cm3. Clinical optimization times for the hybrid plans are still under one minute, for most cases. It is possible to generate clinically advantageous brachytherapy plans (i.e. obtain the same quality dose distribution as a standard single-activity plan) while incorporating leftover seeds from a previous patient treatment. This method will allow a clinic to continue to provide excellent patient care, but at a reduced cost. Multi-activity hybrid plans were equal in quality (as measured by the standard dosimetric indices) to plans with seeds of a single activity. Despite the expanded search space, optimization times for these studies were still under two minutes on a modern day laptop and can be reduced to below one minute in a clinical setting

  18. Impact of short course hormonal therapy on overall and cancer specific survival after permanent prostate brachytherapy

    SciTech Connect

    Beyer, David C. . E-mail: dbeyer@azoncology.com; McKeough, Timothy; Thomas, Theresa

    2005-04-01

    Purpose: To review the impact of prior hormonal therapy on 10-year overall and prostate cancer specific survival after primary brachytherapy. Methods and Materials: A retrospective review was performed on the Arizona Oncology Services tumor registry for 2,378 consecutive permanent prostate brachytherapy cases from 1988 through 2001. Hormonal therapy was administered before the implant in 464 patients for downsizing of the prostate or at the discretion of the referring physician. All deceased patients with known clinical recurrence were considered to have died of prostate cancer, irrespective of the immediate cause of death. Risk groups were defined, with 1,135 favorable (prostate-specific antigen [PSA] < 10, Gleason < 7, Stage T1-T2a), 787 intermediate (single adverse feature), and 456 unfavorable (two or more adverse features) patients. Kaplan-Meier actuarial survival curves were generated for both overall and cause-specific survival from the time of treatment. Multivariate analysis was performed to assess the impact of hormonal intervention in comparison with known risk factors of grade, PSA, and age. Results: With follow-up ranging up to 12.6 years and a median of 4.1 year, a total of 474 patients died, with 67 recorded as due to prostate cancer. Overall and cause-specific 10-year survival rates are 43% and 88%, respectively. Overall survival is 44% for the hormone naive patients, compared with 20% for the hormone-treated cohort (p = 0.02). The cancer-specific survival is 89% vs. 81% for the same groups (p = 0.133). Multivariate analysis confirms the significance of age > 70 years (p = 0.0013), Gleason score {>=} 7 (p = 0.0005), and prior hormone use (p = 0.0065) on overall survival. Conclusions: At 10 years, in prostate cancer patients receiving brachytherapy, overall survival is worse in men receiving neoadjuvant hormonal therapy, compared with hormone naive patients. This does not appear to be due to other known risk factors for survival (i.e., stage, grade

  19. Customized Dose Prescription for Permanent Prostate Brachytherapy: Insights From a Multicenter Analysis of Dosimetry Outcomes

    SciTech Connect

    Stone, Nelson N. Potters, Louis; Davis, Brian J.; Ciezki, Jay P.; Zelefsky, Michael J.; Roach, Mack; Fearn, Paul A. B.A.; Kattan, Michael W.; Stock, Richard G.

    2007-12-01

    Purpose: To investigate the biochemical control rate in patients undergoing permanent prostate brachytherapy as a function of the biologically effective dose (BED) and risk group. Methods and Materials: Six centers provided data on 3,928 permanent brachytherapy patients with postimplant dosimetry results. The mean prostate-specific antigen level was 8.9 ng/mL. {sup 125}I was used in 2,293 (58%), {sup 103}Pd in 1,635, and supplemental external beam radiotherapy in 882 (22.5%) patients. The patients were stratified into low- (n = 2,188), intermediate- (n = 1,188), and high- (n = 552) risk groups and into three BED groups of < 140 Gy (n = 524), 140-200 Gy (n = 2284), and >200 Gy (n = 1,115). Freedom from biochemical disease progression (biochemical freedom from failure [bFFF]) was determined using the American Society for Therapeutic Radiology Oncology and Phoenix definitions and calculated using the Kaplan-Meier method, with factors compared using the log-rank test. Results: The 10-year prostate-specific antigen bFFF rate for the American Society for Therapeutic Radiology Oncology and Phoenix definitions was 79.2% and 70%, respectively. The corresponding bFFF rates for the low-, intermediate-, and high-risk groups was 84.1% and 78.1%, 76.8% and 63.6%, and 64.4% and 58.2%, respectively (p < 0.0001). The corresponding bFFF rate for the three BED groups was 56.1% and 41.4%, 80% and 77.9%, and 91.1% and 82.9% (p < 0.0001). The corresponding bFFF rate for the low-risk patients by dose group was 69.8% and 49.8%, 86% and 85.2%, and 88.1% and 88.3% for the low-, intermediate, and high-dose group, respectively (p <0.0001). The corresponding bFFF rate for the intermediate-risk patients by dose group was 52.9% and 23.1%, 74.1% and 77.7%, and 94.3% and 88.8% for the low-, intermediate-, and high-dose group, respectively (p < 0.0001). The corresponding bFFF rate for high-risk patients by dose group was 19.2% and 41.7%, 61.8% and 53.2%, and 90% and 69.6% for the low-, intermediate

  20. Sequential evaluation of prostate edema after permanent seed prostate brachytherapy using CT-MRI fusion

    SciTech Connect

    Taussky, Daniel; Austen, Lyn; Toi, Ants; Yeung, Ivan; Williams, Theresa; Pearson, Shannon; McLean, Michael; Pond, Gregory; Crook, Juanita . E-mail: juanita.crook@rmp.uhn.on.ca

    2005-07-15

    Purpose: To analyze the extent and time course of prostate edema and its effect on dosimetry after permanent seed prostate brachytherapy. Methods and Materials: Twenty patients scheduled for permanent seed {sup 125}I prostate brachytherapy agreed to a prospective study on postimplant edema. Implants were preplanned using transrectal ultrasonography. Postimplant dosimetry was calculated using computed tomography-magnetic resonance imaging (CT-MRI) fusion on the day of the implant (Day 1) and Days 8 and 30. The prostate was contoured on MRI, and the seeds were located on CT. Factors investigated for an influence on edema were the number of seeds and needles, preimplant prostate volume, transitional zone index (transition zone volume divided by prostate volume), age, and prostate-specific antigen level. Prostate dosimetry was evaluated by the percentage of the prostate volume receiving 100% of the prescribed dose (V{sub 100}) and percentage of prescribed dose received by 90% of the prostate volume (D{sub 90}). Results: Prostate edema was maximal on Day 1, with the median prostate volume 31% greater than preimplant transrectal ultrasound volume (range, 0.93-1.72; p < 0.001) and decreased with time. It was 21% greater than baseline at Day 8 (p = 0.013) and 5% greater on Day 30 (p < 0.001). Three patients still had a prostate volume greater than baseline by Day 30. The extent of edema depended on the transition zone volume (p = 0.016) and the preplan prostate volume (p 0.003). The median V{sub 100} on Day 1 was 93.6% (range, 86.0-98.2%) and was 96.3% (range, 85.7-99.5%) on Day 30 (p = 0.079). Patients with a Day 1 V{sub 100} >93% were less affected by edema resolution, showing a median increase in V{sub 100} of 0.67% on Day 30 compared with 2.77% for patients with a V{sub 100} <93 % on Day 1. Conclusion: Despite the extreme range of postimplant edema, the effect on dosimetry was less than expected. Dose coverage of the prostate was good for all patients during Days 1

  1. [Intraoperative and post-implant dosimetry in patients treated with permanent prostate implant brachytherapy].

    PubMed

    Herein, András; Ágoston, Péter; Szabó, Zoltán; Jorgo, Kliton; Markgruber, Balázs; Pesznyák, Csilla; Polgár, Csaba; Major, Tibor

    2015-06-01

    The purpose of our work was to compare intraoperative and four-week post-implant dosimetry for loose and stranded seed implants for permanent prostate implant brachytherapy. In our institute low-dose-rate (LDR) prostate brachytherapy is performed with encapsulated I-125 isotopes (seeds) using transrectal ultrasound guidance and metal needles. The SPOT PRO 3.1 (Elekta, Sweden) system is used for treatment planning. In this study the first 79 patients were treated with loose seed (LS) technique, the consecutive patients were treated with stranded seed (SS) technique. During intraoperative planning the dose constraints were the same for both techniques. All LSs were placed inside the prostate capsule, while with SS a 2 mm margin around the prostate was allowed for seed positioning. The prescribed dose for the prostate was 145 Gy. This study investigated prostate dose coverage in 30-30 randomly selected patients with LS and SS. Four weeks after the implantation native CT and MRI were done and CT/MRI image fusion was performed. The target was contoured on MRI and the plan was prepared on CT data. To assess the treatment plan dose-volume histograms were used. For the target coverage V100, V90, D90, D100, for the dose inhomogeneity V150, V200, and the dose-homogeneity index (DHI), for dose conformality the conformal index (COIN) were calculated. Intraoperative and postimplant plans were compared. The mean V100 values decreased at four-week plan for SS (97% vs. 84%) and for LS (96% vs. 80%) technique, as well. Decrease was observed for all parameters except for the DHI value. The DHI increased for SS (0.38 vs. 0.41) and for LS (0.38 vs. 0.47) technique, as well. The COIN decreased for both techniques at four-week plan (SS: 0.63 vs. 0.57; LS: 0.67 vs. 0.50). All differences were significant except for the DHI value at SS technique. The percentage changes were not significant, except the COIN value. The dose coverage of the target decreased significantly at four-week plans

  2. American Society for Radiation Oncology (ASTRO) and American College of Radiology (ACR) Practice Guideline for the Transperineal Permanent Brachytherapy of Prostate Cancer

    SciTech Connect

    Rosenthal, Seth A.; Bittner, Nathan H.J.; Demanes, D. Jeffrey; Goldsmith, Brian J.; Horwitz, Eric M.; Ibbott, Geoffrey S.; Lee, W. Robert; Nag, Subir; Suh, W. Warren; Potters, Louis

    2011-02-01

    Transperineal permanent prostate brachytherapy is a safe and efficacious treatment option for patients with organ-confined prostate cancer. Careful adherence to established brachytherapy standards has been shown to improve the likelihood of procedural success and reduce the incidence of treatment-related morbidity. A collaborative effort of the American College of Radiology (ACR) and American Society for Therapeutic Radiation Oncology (ASTRO) has produced a practice guideline for permanent prostate brachytherapy. The guideline defines the qualifications and responsibilities of all the involved personnel, including the radiation oncologist, physicist and dosimetrist. Factors with respect to patient selection and appropriate use of supplemental treatment modalities such as external beam radiation and androgen suppression therapy are discussed. Logistics with respect to the brachtherapy implant procedure, the importance of dosimetric parameters, and attention to radiation safety procedures and documentation are presented. Adherence to these practice guidelines can be part of ensuring quality and safety in a successful prostate brachytherapy program.

  3. Radioimmunoguided surgery using iodine 125 B72. 3 in patients with colorectal cancer

    SciTech Connect

    Cohen, A.M.; Martin, E.W. Jr.; Lavery, I.; Daly, J.; Sardi, A.; Aitken, D.; Bland, K.; Mojzisik, C.; Hinkle, G. )

    1991-03-01

    Preliminary data using B72.3 murine monoclonal antibody labeled with iodine 125 suggested that both clinically apparent as well as occult sites of colorectal cancer could be identified intraoperatively using a hand-held gamma detecting probe. We report the preliminary data of a multicenter trial of this approach in patients with primary or recurrent colorectal cancer. One hundred four patients with primary, suspected, or known recurrent colorectal cancer received an intravenous infusion of 1 mg of B72.3 monoclonal antibody radiolabeled with 7.4 x 10 Bq of iodine 125. Twenty-six patients with primary colorectal cancer and 72 patients with recurrent colorectal cancer were examined. Using the gamma detecting probe, 78% of the patients had localization of the antibody in their tumor; this included 75% of primary tumor sites and 63% of all recurrent tumor sites; 9.2% of all tumor sites identified represented occult sites detected only with the gamma detecting probe. The overall sensitivity was 77% and a predictive value of a positive detection was 78%. A total of 30 occult sites in 26 patients were identified. In patients with recurrent cancer, the antibody study provided unique data that precluded resection in 10 patients, and in another eight patients it extended the potentially curative procedure.

  4. Dosimetric study of Cs-131, I-125, and Pd-103 seeds for permanent prostate brachytherapy.

    PubMed

    Yang, Ruijie; Wang, Junjie; Zhang, Hongzhi

    2009-12-01

    As a well-established single-modality approach for early-stage prostate cancer, transperineal interstitial permanent prostate brachytherapy (TIPPB) has gained increasing popularity due to its favorable clinical results. Currently, three isotopes, namely Cs-131, I-125, and Pd-103, are commercially available for TIPPB. This is the first study to systematically explore the dosimetric difference of these three isotopes for TIPPB. In total, 25 patients with T1-T2c prostate cancer previously implanted with I-125 seeds were randomly selected and replanned with Cs-131, I-125, and Pd-103 seeds to the prescription doses of 115, 145, and 125 Gy, respectively. The planning goals attempted were prostate V(p)100 approximately 95%, D(p)90 >or= 100%, and prostatic urethra D(u)10

  5. Iodine-125 cholesteryl iopanoate for measuring extent of atherosclerosis in rabbits.

    PubMed

    DeGalan, M R; Schwendner, S W; Skinner, R W; Longino, M A; Gross, M; Counsell, R E

    1988-04-01

    Rabbits rendered atherosclerotic by mechanical aortic de-endothelialization and 6 wk of cholesterol feeding were administered estradiol-17 beta-cypionate, an anti-atherogenic agent in rabbits. These animals were compared to a similar, untreated group and control animals fed a regular non-atherogenic diet. Iodine-125 cholesteryl iopanoate ([125I]Cl), a nonhydrolyzable cholesteryl ester derivative, was administered intravenously at regular intervals throughout the study. Six days after the last dose of [125I]Cl, the animals were scanned with a gamma camera. After animals were killed, tissue distribution of the 125I radioactivity showed a significant decrease of [125I]CI accumulation in the aorta of estrogen-treated as compared to untreated, cholesterol-fed animals. However, the accumulation of [125I]CI in the aortas was insufficient to accurately define the presence of atheroma by gamma camera scintigraphy.

  6. SU-F-19A-08: Optimal Time Release Schedule of In-Situ Drug Release During Permanent Prostate Brachytherapy

    SciTech Connect

    Cormack, R; Ngwa, W; Makrigiorgos, G; Tangutoori, S; Rajiv, K; Sridhar, S

    2014-06-15

    Purpose: Permanent prostate brachytherapy spacers can be used to deliver sustained doses of radiosentitizing drug directly to the target, in order to enhance the radiation effect. Implantable nanoplatforms for chemo-radiation therapy (INCeRTs) have a maximum drug capacity and can be engineered to control the drug release schedule. The optimal schedule for sensitization during continuous low dose rate irradiation is unknown. This work studies the optimal release schedule of drug for both traditional sensitizers, and those that work by suppressing DNA repair processes. Methods: Six brachytherapy treatment plans were used to model the anatomy, implant geometry and calculate the spatial distribution of radiation dose and drug concentrations for a range of drug diffusion parameters. Three state partial differential equations (cells healthy, damaged or dead) modeled the effect of continuous radiation (radiosensitivities α,β) and cellular repair (time tr) on a cell population. Radiosensitization was modeled as concentration dependent change in α,β or tr which with variable duration under the constraint of fixed total drug release. Average cell kill was used to measure effectiveness. Sensitization by means of both enhanced damage and reduced repair were studied. Results: Optimal release duration is dependent on the concentration of radiosensitizer compared to the saturation concentration (csat) above which additional sensitization does not occur. Long duration drug release when enhancing α or β maximizes cell death when drug concentrations are generally over csat. Short term release is optimal for concentrations below saturation. Sensitization by suppressing repair has a similar though less distinct trend that is more affected by the radiation dose distribution. Conclusion: Models of sustained local radiosensitization show potential to increase the effectiveness of radiation in permanent prostate brachytherapy. INCeRTs with high drug capacity produce the greatest

  7. Isotope and Patient Age Predict for PSA Spikes After Permanent Prostate Brachytherapy

    SciTech Connect

    Bostancic, Chelsea; Merrick, Gregory S. . E-mail: gmerrick@urologicresearchinstitute.org; Butler, Wayne M.; Wallner, Kent E.; Allen, Zachariah; Galbreath, Robert; Lief, Jonathan; Gutman, Sarah E.

    2007-08-01

    Purpose: To evaluate prostate-specific antigen (PSA) spikes after permanent prostate brachytherapy in low-risk patients. Methods and Materials: The study population consisted of 164 prostate cancer patients who were part of a prospective randomized trial comparing {sup 103}Pd and {sup 125}I for low-risk disease. Of the 164 patients, 61 (37.2%) received short-course androgen deprivation therapy. The median follow-up was 5.4 years. On average, 11.1 post-treatment PSA measurements were obtained per patient. Biochemical disease-free survival was defined as a PSA level of {<=}0.40 ng/mL after nadir. A PSA spike was defined as an increase of {>=}0.2 ng/mL, followed by a durable decline to prespike levels. Multiple parameters were evaluated as predictors for a PSA spike. Results: Of the 164 patients, 44 (26.9%) developed a PSA spike. Of the 46 hormone-naive {sup 125}I patients and 57 hormone-naive {sup 103}Pd patients, 21 (45.7%) and 8 (14.0%) developed a PSA spike. In the hormone-naive patients, the mean time between implantation and the spike was 22.6 months and 18.7 months for {sup 125}I and {sup 103}Pd, respectively. In patients receiving neoadjuvant androgen deprivation therapy, the incidence of spikes was comparable between isotopes ({sup 125}I 28.1% and {sup 103}Pd 20.7%). The incidence of spikes was substantially different in patients <65 years vs. {>=}65 years old (38.5% vs. 16.3%). On multivariate Cox regression analysis, patient age (p < 0.001) and isotope (p = 0.002) were significant predictors for spike. Conclusion: In low-risk prostate cancer, PSA spikes are most common in patients implanted with {sup 125}I and/or <65 years of age. Differences in isotope-related spikes are most pronounced in hormone-naive patients.

  8. Urethra-Sparing, Intraoperative, Real-Time Planned, Permanent-Seed Prostate Brachytherapy: Toxicity Analysis

    SciTech Connect

    Zilli, Thomas; Taussky, Daniel; Donath, David; Le, Hoa Phong; Larouche, Renee-Xaviere; Beliveau-Nadeau, Dominique; Hervieux, Yannick; Delouya, Guila

    2011-11-15

    Purpose: To report the toxicity outcome in patients with localized prostate cancer undergoing {sup 125}I permanent-seed brachytherapy (BT) according to a urethra-sparing, intraoperative (IO), real-time planned conformal technique. Methods and Materials: Data were analyzed on 250 patients treated consecutively for low- or intermediate-risk prostate cancer between 2005 and 2009. The planned goal was urethral V{sub 150} = 0. Acute and late genitourinary (GU), gastrointestinal (GI), and erectile toxicities were scored with the International Prostate Symptom Score (IPSS) questionnaire and Common Terminology Criteria for Adverse Events (version 3.0). Median follow-up time for patients with at least 2 years of follow-up (n = 130) was 34.4 months (range, 24-56.9 months). Results: Mean IO urethra V{sub 150} was 0.018% {+-} 0.08%. Mean prostate D{sub 90} and V{sub 100} on day-30 computed tomography scan were 158.0 {+-} 27.0 Gy and 92.1% {+-} 7.2%, respectively. Mean IPSS peak was 9.5 {+-} 6.3 1 month after BT (mean difference from baseline IPSS, 5.3). No acute GI toxicity was observed in 86.8% of patients. The 3-year probability of Grade {>=}2 late GU toxicity-free survival was 77.4% {+-} 4.0%, with Grade 3 late GU toxicity encountered in only 3 patients. Three-year Grade 1 late GI toxicity-free survival was 86.1% {+-} 3.2%. No patient presented Grade {>=}2 late GI toxicity. Of patients with normal sexual status at baseline, 20.7% manifested Grade {>=}2 erectile dysfunction after BT. On multivariate analysis, elevated baseline IPSS (p = 0.016) and high-activity sources (median 0.61 mCi) (p = 0.033) predicted increased Grade {>=}2 late GU toxicity. Conclusions: Urethra-sparing IO BT results in low acute and late GU toxicity compared with the literature. High seed activity and elevated IPSS at baseline increased long-term GU toxicity.

  9. SU-E-T-123: Anomalous Altitude Effect in Permanent Implant Brachytherapy Seeds

    SciTech Connect

    Watt, E; Spencer, DP; Meyer, T

    2015-06-15

    Purpose: Permanent seed implant brachytherapy procedures require the measurement of the air kerma strength of seeds prior to implant. This is typically accomplished using a well-type ionization chamber. Previous measurements (Griffin et al., 2005; Bohm et al., 2005) of several low-energy seeds using the air-communicating HDR 1000 Plus chamber have demonstrated that the standard temperature-pressure correction factor, P{sub TP}, may overcompensate for air density changes induced by altitude variations by up to 18%. The purpose of this work is to present empirical correction factors for two clinically-used seeds (IsoAid ADVANTAGE™ {sup 103}Pd and Nucletron selectSeed {sup 125}I) for which empirical altitude correction factors do not yet exist in the literature when measured with the HDR 1000 Plus chamber. Methods: An in-house constructed pressure vessel containing the HDR 1000 Plus well chamber and a digital barometer/thermometer was pumped or evacuated, as appropriate, to a variety of pressures from 725 to 1075 mbar. Current measurements, corrected with P{sub TP}, were acquired for each seed at these pressures and normalized to the reading at ‘standard’ pressure (1013.25 mbar). Results: Measurements in this study have shown that utilization of P{sub TP} can overcompensate in the corrected current reading by up to 20% and 17% for the IsoAid Pd-103 and the Nucletron I-125 seed respectively. Compared to literature correction factors for other seed models, the correction factors in this study diverge by up to 2.6% and 3.0% for iodine (with silver) and palladium respectively, indicating the need for seed-specific factors. Conclusion: The use of seed specific altitude correction factors can reduce uncertainty in the determination of air kerma strength. The empirical correction factors determined in this work can be applied in clinical quality assurance measurements of air kerma strength for two previously unpublished seed designs (IsoAid ADVANTAGE™ {sup 103}Pd and

  10. Brachytherapy optimization using radiobiological-based planning for high dose rate and permanent implants for prostate cancer treatment

    NASA Astrophysics Data System (ADS)

    Seeley, Kaelyn; Cunha, J. Adam; Hong, Tae Min

    2017-01-01

    We discuss an improvement in brachytherapy--a prostate cancer treatment method that directly places radioactive seeds inside target cancerous regions--by optimizing the current standard for delivering dose. Currently, the seeds' spatiotemporal placement is determined by optimizing the dose based on a set of physical, user-defined constraints. One particular approach is the ``inverse planning'' algorithms that allow for tightly fit isodose lines around the target volumes in order to reduce dose to the patient's organs at risk. However, these dose distributions are typically computed assuming the same biological response to radiation for different types of tissues. In our work, we consider radiobiological parameters to account for the differences in the individual sensitivities and responses to radiation for tissues surrounding the target. Among the benefits are a more accurate toxicity rate and more coverage to target regions for planning high-dose-rate treatments as well as permanent implants.

  11. Permanent Prostate Brachytherapy in Prostate Glands <20 cm{sup 3}

    SciTech Connect

    Mayadev, Jyoti; Merrick, Gregory S.; Reed, Joshua R.; Butler, Wayne M.; Galbreath, Robert W.; Allen, Zachariah A.; Wallner, Kent E.

    2010-04-15

    Purpose: To investigate the dosimetry, treatment-related morbidity, and biochemical outcomes for brachytherapy in patients with prostate glands <20 cm{sup 3}. Methods and Materials: From November 1996 to October 2006, 104 patients with prostate glands <20 cm{sup 3} underwent brachytherapy. Multiple prostate, urethral, and rectal dosimetric parameters were evaluated. Treatment-related urinary and rectal morbidity were assessed from patient questionnaires. Cause-specific survival, biochemical progression-free survival, and overall survival were recorded. Results: The median patient age, follow up, and pre-treatment ultrasound volume was 64 years, 5.0 years and 17.6cm{sup 3}, respectively. Median day 0 dosimetry was significant for the following: V100 98.5%, D90 126.1% and R100 <0.5% of prescription dose. The mean urethral and maximum urethral doses were 119.6% and 133.8% of prescription. The median time to International Prostate Symptom Score resolution was 4 months. There were no RTOG grade III or IV rectal complications. The cause-specific survival, biochemical progression-free survival, and overall survival rates were 100%, 92.5%, and 77.8% at 9 years. For biochemically disease-free patients, the median most recent postbrachytherapy PSA value was 0.02 ng/mL. Conclusion: Our results demonstrate that brachytherapy for small prostate glands is highly effective, with an acceptable morbidity profile, excellent postimplant dosimetry, acceptable treatment-related morbidity, and favorable biochemical outcomes.

  12. SU-F-BRA-03: Integrating Novel Electromagnetic Tracking Hollow Needle Assistance in Permanent Implant Brachytherapy Procedures

    SciTech Connect

    Racine, E; Hautvast, G; Binnekamp, D; Beaulieu, L

    2015-06-15

    Purpose: To report on the results of a complete permanent implant brachytherapy procedure assisted by an electromagnetic (EM) hollow needle possessing both 3D tracking and seed drop detection abilities. Methods: End-to-end in-phantom EM-assisted LDR procedures were conducted. The novel system consisted of an EM tracking apparatus (NDI Aurora V2, Planar Field Generator), a 3D US scanner (Philips CX50), a hollow needle prototype allowing 3D tracking and seed drop detection and a specially designed treatment planning software (Philips Healthcare). A tungsten-doped 30 cc spherical agarose prostate immersed in gelatin was used for the treatment. A cylindrical shape of 0.8 cc was carved along its diameter to mimic the urethra. An initial plan of 26 needles and 47 seeds was established with the system. The plan was delivered with the EM-tracked hollow needle, and individual seed drop locations were recorded on the fly. The phantom was subsequently imaged with a CT scanner from which seed positions and contour definitions were obtained. The DVHs were then independently recomputed and compared with those produced by the planning system, both before and after the treatment. Results: Of the 47 seeds, 45 (96%) were detected by the EM technology embedded in the hollow needle design. The executed plan (from CT analysis) differed from the initial plan by 2%, 14% and 8% respectively in terms of V100, D90 and V150 for the prostate, and by 8%, 7% and 10% respectively in terms of D5, V100 and V120 for the urethra. Conclusion: The average DVH deviations between initial and executed plans were within a 5% tolerance imposed for this proof-of-concept assessment. This relatively good concordance demonstrates the feasibility and potential benefits of combining EM tracking and seed drop detection for real-time dosimetry validation and assistance in permanent implant brachytherapy procedures. This project has been entirely funded by Philips Healthcare.

  13. Iodine-125 implant and external beam irradiation in patients with localized pancreatic carcinoma. [Efficacy and complications

    SciTech Connect

    Shipley, W.U.; Nardi, G.L.; Cohen, A.M.; Ling, C.C.

    1980-02-15

    Twelve patients with biopsy-proven clinically localized ductal pancreatic cancers (less than 7 cm in greatest diameter) judged unsuitable for resection were treated by bypass surgery, an Iodine-125 implant (20 to 39 mCi), and postoperative irradiation (4000 to 4500 rads). The potential problems of significant bleeding, pancreatic fistula, or pancreatitis were not experienced. A local recurrence developed in one patient and two recurred in regional lymph nodes. The projected median survival of the group is 11 months with four of the 12 patients still surviving. For purposes of comparison all patients with pancreatic ductal carcinoma treated by radical resection during a similar time were evaluated. All ten have died with a median survival of six months. Twelve of 22 (55%) of the combined implanted and resected groups have developed distant metastasis. Further pursuit of intraoperative techniques of irradiation in combination with adjuvant multidrug chemotherapy seems indicated in an attempt to prolong patient survival which is now limited by hematogenous metastases.

  14. Distant Metastases Following Permanent Interstitial Brachytherapy for Patients With Clinically Localized Prostate Cancer

    SciTech Connect

    Taira, Al V.; Merrick, Gregory S.; Galbreath, Robert W.; Butler, Wayne M.; Lief, Jonathan; Adamovich, Edward; Wallner, Kent E.

    2012-02-01

    Purpose: Recent publications have suggested high-risk patients undergoing radical prostatectomy have a lower risk of distant metastases and improved cause-specific survival (CSS) than patients receiving definitive external beam radiation therapy (XRT). To date, none of these studies has compared distant metastases and CSS in brachytherapy patients. In this study, we evaluate such parameters in a consecutive cohort of brachytherapy patients. Methods and Materials: From April 1995 to June 2007, 1,840 consecutive patients with clinically localized prostate cancer were treated with brachytherapy. Risk groups were stratified according to National Comprehensive Cancer Network ( (www.nccn.org)) guidelines. Subgroups of 658, 893, and 289 patients were assigned to low, intermediate, and high-risk categories. Median follow-up was 7.2 years. Along with brachytherapy implantation, 901 (49.0%) patients received supplemental XRT, and 670 (36.4%) patients received androgen deprivation therapy (median duration, 4 months). The mode of failure (biochemical, local, or distant) was determined for each patient for whom therapy failed. Cause of death was determined for each deceased patient. Multiple parameters were evaluated for impact on outcome. Results: For the entire cohort, metastases-free survival (MFS) and CSS at 12 years were 98.1% and 98.2%, respectively. When rates were stratified by low, intermediate, and high-risk groups, the 12-year MFS was 99.8%, 98.1%, and 93.8% (p < 0.001), respectively. CSS rates were 99.8%, 98.0%, and 95.3% (p < 0.001) for low, intermediate, and high-risk groups, respectively. Biochemical progression-free survival was 98.7%, 95.9% and 90.4% for low, intermediate, and high-risk patients, respectively (p < 0.001). In multivariate Cox-regression analysis, MFS was mostly closely related to Gleason score and year of treatment, whereas CSS was most closely associated with Gleason score. Conclusions: Excellent CSS and MFS rates are achievable with high

  15. Method for the simultaneous preparation of Radon-211, Xenon-125, Xenon-123, Astatine-211, Iodine-125 and Iodine-123

    DOEpatents

    Mirzadeh, Saed; Lambrecht, Richard M.

    1987-01-01

    A method for simultaneously preparing Radon-211, Astatine-211, Xenon-125, Xenon-123, Iodine-125 and Iodine-123 in a process that includes irradiating a fertile metal material then using a one-step chemical procedure to collect a first mixture of about equal amounts of Radon-211 and Xenon-125, and a separate second mixture of about equal amounts of Iodine-123 and Astatine-211.

  16. The use of iodine-125 seeds as a substitute for iridium-192 seeds in temporary interstitial breast implants

    SciTech Connect

    Vicini, F.; White, J.; Gustafson, G.; Matter, R.C.; Edmundson, G.; Martinez, A.; Clarke, D.H.

    1993-10-20

    We have previously reported that the use of iodine-125 seeds in temporary plastic tube interstitial implants may be more advantageous than iridium-192 seeds due to less patient and personnel radiation exposure, reduced shielding requirements, and significant dosimetric advantages. The impact of this isotope on the rate of local control and cosmetic outcome in patients with early stage breast cancer treated with interstitial implants for their irradiation {open_quotes}boost{close_quotes} remains to be defined. We reviewed the treatment outcome of 402 consecutive cases of Stage I and II breast cancer undergoing breast conserving therapy between 1/1/80 and 12/31/87. All patients underwent excisional biopsy and received 45-50 Gy to the entire breast followed by a boost to the tumor bed using either electrons (104 patients), photons (15 patients), or an interstitial implant with either iridium-192 (197 patients) or iodine-125 (86 patients) to at least 60 Gy. Iodine-125 implants were primarily performed in patients with significant risk factors for local recurrence (71%) or in patients with large breasts (17%). Local tumor control and cosmetic outcome were assessed and contrasted between patients boosted with each modality. We conclude that patients with State I and II breast cancer undergoing breast conserving therapy and judged to be candidates for boosts with interstitial implants can be effectively treated with iodine-125 seeds. Use of the isotope results in less patient and personnel irradiation exposure and a better dose distribution than iridium-192, since dose optimization can be routinely employed. Overall, local control and cosmetic outcome have been excellent and are similar to either iridium-192, electrons, or photons. 21 refs., 4 tabs.

  17. Continuous Low-dose-rate Irradiation of Iodine-125 Seeds Inhibiting Perineural Invasion in Pancreatic Cancer

    PubMed Central

    Lu, Zheng; Dong, Teng-Hui; Si, Pei-Ren; Shen, Wei; Bi, Yi-Liang; Min, Min; Chen, Xin; Liu, Yan

    2016-01-01

    Background: Perineural invasion (PNI) is a histopathological characteristic of pancreatic cancer (PanCa). The aim of this study was to observe the treatment effect of continuous low-dose-rate (CLDR) irradiation to PNI and assess the PNI-related pain relief caused by iodine-125 (125I) seed implantation. Methods: The in vitro PNI model established by co-culture with dorsal root ganglion (DRG) and cancer cells was interfered under 2 and 4 Gy of 125I seeds CLDR irradiation. The orthotopic models of PNI were established, and 125I seeds were implanted in tumor. The PNI-related molecules were analyzed. In 30 patients with panCa, the pain relief was assessed using a visual analog scale (VAS). Pain intensity was measured before and 1 week, 2 weeks, and 1, 3, and 6 months after 125I seed implantation. Results: The co-culture of DRG and PanCa cells could promote the growth of PanCa cells and DRG neurites. In co-culture groups, the increased number of DRG neurites and pancreatic cells in radiation group was significantly less. In orthotopic models, the PNI-positive rate in radiation and control group was 3/11 and 7/11; meanwhile, the degrees of PNI between radiation and control groups was significant difference (P < 0.05). At week 2, the mean VAS pain score in patients decreased by 50% and significantly improved than the score at baseline (P < 0.05). The pain scores were lower in all patients, and the pain-relieving effect was retained about 3 months. Conclusions: The CLDR irradiation could inhibit PNI of PanCa with the value of further study. The CLDR irradiation could do great favor in preventing local recurrence and alleviating pain. PMID:27748339

  18. Iodine-125-labeled cRGD-gold nanoparticles as tumor-targeted radiosensitizer and imaging agent

    NASA Astrophysics Data System (ADS)

    Su, Ning; Dang, Yajie; Liang, Guangli; Liu, Guizhi

    2015-04-01

    Research interests on radiosensitive property of gold nanoparticles (GNPs) are rapidly raised because of the extensively proved in vitro effectiveness and clinical necessity. However, the issue of targeted accumulation of GNPs in tumor tissues hindered the transference to in vivo applications. In this study, hybrid nano-sized cyclic Arg-Gly-Asp-conjugated GNPs (cRGD-GNPs) integrated with radioactive iodine-125 was fabricated as tumor-targeted radiosensitizer. Therapeutic effects, including acute apoptosis (2 days post treatment) and long-term influence (up to 21 days), were investigated on NCI-H446 tumor-bearing mice via Tc-99 m-Annexin V SPECT and volume measurements, respectively. Apoptosis and volume loss were consistent in showing that tumor growth was effectively suppressed via the treatment of 125I-cRGD-GNP sensitized radiotherapy (RT), a more significantly radiosensitive effect than the treatment of non-targeted GNPs with RT, RT treatment alone, and no treatment. SPECT/CT images showed that the uptake of cRGD-GNPs by tumor tissues reached the peak target/non-target value of 4.76 at around 2 h post injection, and dynamic radioactivity monitoring showed that 125I-cRGD-GNPs maintained about 2.5% of injected dosage at 55 h post injection. For long-term influence, a significant radiosensitized RT-induced volume loss was observed. Hence, cyclic RGD conjugation makes the GNP-based radiosensitizer tumor targeting, offering a new modality for enhancing radiotherapeutic efficacy. Additionally, the introduction of I-125 serves as both a therapeutic factor and a radiotracer for in vivo tracking of GNPs.

  19. Source strength assay of iodine-125 seeds sealed within sterile packaging.

    PubMed

    Otani, Yuki; Yamada, Takahiro; Kato, Shingo; Shikama, Naoto; Funakoshi, Kazuto; Kuroda, Isao; Numasaki, Hodaka; Nose, Takayuki; Dokiya, Takushi; Oguchi, Masahiko

    2013-03-04

    Early-stage prostate cancer is widely treated by iodine-125 (I-125) seed implantation. While quality assurance methods are in place to assure consistency in I-125 seed source strength, current methods involve the breaking of the sterilization package, raising issues concerning sterility and time limitations. The purpose of this study was to develop a method of characterizing the total source strength of I-125 seeds within a cartridge that has been sealed within a sterilization package and to evaluate the probability of detecting an out-of-calibration seed (aberrant seed). We defined a protocol to determine the ability of a well-type ionization chamber to detect aberrant I-125 seeds within a cartridge sealed in the sterilization package. A novel jig for a well-type ionization chamber was designed to accommodate the sterilization package. One seed was chosen randomly from two cartridges containing five or 15 seeds (0.544 U source strength) and was exchanged with aberrant seeds of six different source strengths. The source strength was measured at each position within the cartridge. The results indicated that the response of the well chamber was sensitive to changes in the aberrant seed position within the cartridge and the source strength of the aberrant seed. The correlation coefficient between single seed and batch assay results was high (0.998). A novel jig and a measurement method using a well ionization chamber were developed, which allowed for a batch assay characterization of the total source strength of I-125 seeds within a cartridge sealed within sterilization package. This method is simple, time-saving, and offers greater practical application.

  20. Metallic artifact mitigation and organ-constrained tissue assignment for Monte Carlo calculations of permanent implant lung brachytherapy

    SciTech Connect

    Sutherland, J. G. H.; Miksys, N.; Thomson, R. M.; Furutani, K. M.

    2014-01-15

    assignment within lung contours are employed in generated phantoms, this erroneous assignment is reduced, generally resulting in higher doses. Lung-constrained tissue assignment also results in increased doses in regions of interest due to a reduction in the erroneous assignment of adipose to voxels within lung contours. Differences in dose metrics calculated for different computational phantoms are sensitive to radionuclide photon spectra with the largest differences for{sup 103}Pd seeds and smallest but still considerable differences for {sup 131}Cs seeds. Conclusions: Despite producing differences in CT images, dose metrics calculated using the STR, fan beam + STR, and 3D median filter techniques produce similar dose metrics. Results suggest that the accuracy of dose distributions for permanent implant lung brachytherapy is improved by applying lung-constrained tissue assignment schemes to metallic artifact corrected images.

  1. Natural History of Clinically Staged Low- and Intermediate-Risk Prostate Cancer Treated With Monotherapeutic Permanent Interstitial Brachytherapy

    SciTech Connect

    Taira, Al V.; Merrick, Gregory S.; Galbreath, Robert W.; Wallner, Kent E.; Butler, Wayne M.

    2010-02-01

    Purpose: To evaluate the natural history of clinically staged low- and intermediate-risk prostate cancer treated with permanent interstitial seed implants as monotherapy. Methods and Materials: Between April 1995 and May 2005, 463 patients with clinically localized prostate cancer underwent brachytherapy as the sole definitive treatment. Men who received supplemental external beam radiotherapy or androgen deprivation therapy were excluded. Dosimetric implant quality was determined based on the minimum dose that covered 90% of the target volume and the volume of the prostate gland receiving 100% of the prescribed dose. Multiple parameters were evaluated as predictors of treatment outcomes. Results: The 12-year biochemical progression-free survival (bPFS), cause-specific survival, and overall survival rates for the entire cohort were 97.1%, 99.7%, and 75.4%, respectively. Only pretreatment prostate-specific antigen level, percent positive biopsy cores, and minimum dose that covered 90% of the target volume were significant predictors of biochemical recurrence. The bPFS, cause-specific survival, and overall survival rates were 97.4%, 99.6%, and 76.2%, respectively, for low-risk patients and 96.4%, 100%, and 74.0%, respectively, for intermediate-risk patients. The bPFS rate was 98.8% for low-risk patients with high-quality implants versus 92.1% for those with less adequate implants (p < 0.01), and it was 98.3% for intermediate-risk patients with high-quality implants versus 86.4% for those with less adequate implants (p < 0.01). Conclusions: High-quality brachytherapy implants as monotherapy can provide excellent outcomes for men with clinically staged low- and intermediate-risk prostate cancer. For these men, a high-quality implant can achieve results comparable to high-quality surgery in the most favorable pathologically staged patient subgroups.

  2. Evaluation of dosimetry and excess seeds in permanent brachytherapy using a modified hybrid method: a single-institution experience.

    PubMed

    Kobayashi, Kana; Okihara, Koji; Iwata, Tsuyoshi; Aibe, Norihiro; Kodani, Naohiro; Tsubokura, Takuji; Kamoi, Kazumi; Miki, Tsuneharu; Yamazaki, Hideya

    2013-05-01

    Permanent prostate brachytherapy is frequently performed worldwide, and many studies have demonstrated its favorable outcomes. Implant seeds used in this procedure contain a precise amount of radionuclide and are completely sealed. Because these seeds are not manufactured in Japan, they are expensive (6300 yen per seed) and therefore need careful management as a radioisotope. The proper implantation technique requires considerable procedure time, good dosimetric outcomes and simple radioactive isotope management. To evaluate the modified hybrid interactive technique based on these considerations, we assessed 313 patients who underwent hybrid interactive brachytherapy without additional external beam radiotherapy. We evaluated the duration of the procedure, dosimetric factors and the total number of excess seeds. The dosimetric results from computed tomography on Day 30 of follow-up were: 172 Gy (range 130-194 Gy) for pD90, 97.8% (83.5-100%) for pV100, 54.6% (27.5-82.4%) for pV150, 164 Gy (120-220 Gy) for uD90, 194 Gy (126-245 Gy) for uD30, 210 Gy (156-290 Gy) for uD5, 0.02 ml (0-1.2 ml) for rV100 and 0 ml (0-0.2 ml) for rV150. The number of excess seeds was determined by subtracting the number of implanted seeds from the expected number of seeds calculated from previously proposed nomograms. As per our method, nine excess seeds were used for two patients, whereas using the nomograms, the number of excess seeds was approximately eight per patient. Our modified hybrid interactive technique reduced the number of excess seeds while maintaining treatment quality.

  3. The impact of prostate edema on cell survival and tumor control after permanent interstitial brachytherapy for early stage prostate cancers

    NASA Astrophysics Data System (ADS)

    (Jay Chen, Zhe; Roberts, Kenneth; Decker, Roy; Pathare, Pradip; Rockwell, Sara; Nath, Ravinder

    2011-08-01

    Previous studies have shown that procedure-induced prostate edema during permanent interstitial brachytherapy (PIB) can cause significant variations in the dose delivered to the prostate gland. Because the clinical impact of edema-induced dose variations strongly depends on the magnitude of the edema, the temporal pattern of its resolution and its interplay with the decay of radioactivity and the underlying biological processes of tumor cells (such as tumor potential doubling time), we investigated the impact of edema-induced dose variations on the tumor cell survival and tumor control probability after PIB with the 131Cs, 125I and 103Pd sources used in current clinical practice. The exponential edema resolution model reported by Waterman et al (1998 Int. J. Radiat. Oncol. Biol. Phys. 41 1069-77) was used to characterize the edema evolutions previously observed during clinical PIB for prostate cancer. The concept of biologically effective dose, taking into account tumor cell proliferation and sublethal damage repair during dose delivery, was used to characterize the effects of prostate edema on cell survival and tumor control probability. Our calculation indicated that prostate edema, if not appropriately taken into account, can increase the cell survival and decrease the probability of local control of PIB. The magnitude of an edema-induced increase in cell survival increased with increasing edema severity, decreasing half-life of radioactive decay and decreasing photon energy emitted by the source. At the doses currently prescribed for PIB and for prostate cancer cells characterized by nominal radiobiology parameters recommended by AAPM TG-137, PIB using 125I sources was less affected by edema than PIB using 131Cs or 103Pd sources due to the long radioactive decay half-life of 125I. The effect of edema on PIB using 131Cs or 103Pd was similar. The effect of edema on 103Pd PIB was slightly greater, even though the decay half-life of 103Pd (17 days) is longer than

  4. Interactive tool for visualization and segmentation of permanent radioactive seeds in postoperative prostate brachytherapy CT images

    NASA Astrophysics Data System (ADS)

    Pathak, Sayan D.; Stoknes, Kevin; Grimm, Peter D.; Estlund, Jacque; Chalana, Vikram; Kim, Yongmin

    1999-05-01

    Implantation of radioactive isotopes within the prostate for the treatment of early stage localized prostate cancer is becoming a popular treatment option. Postoperative calculation of the dose delivered to the prostate requires accurate verification of the number and location of seeds within the prostate. Current post operative dosimetry technique requires the dosimetrist to manually count and record the position of each seed from x-ray computed tomography (CT) images. This procedure is operator-dependent and time-consuming, thus limiting the ability of different brachytherapy centers to compare results and create a standard methodology. Seed identification is performed by thresholding the CT images interactively, using a graphical user interface, followed by mathematical morphology to remove noise. Segmented seeds are grouped into regions via connected-component analysis. Regions are then classified into seeds using a prior knowledge of the seed dimensions and their relative positions in the consecutive CT images. Unresolved regions, which can indicate the presence of more than one seed, are corrected manually. The efficiency of this tool was evaluated by comparing the time to manually count the seeds to the time required to do the same task using the automated program. For 15 sets of images from 15 patients, the average time for manually counting the seeds was 45 minutes per patient versus 6.4 minutes on average per patients, the average time for manually counting the seeds was 45 minutes per patient versus 6.4 minutes on average per patient when the software was used to perform the same task. Using the interactive visualization and segmentation algorithm, the time required to count the seeds during post- implant dosimetry has been reduced by a factor of 7 compared to the existing manual technique.

  5. The tumor control probability model for transperineal permanent prostate brachytherapy and prostate-specific antigen failure free survival

    NASA Astrophysics Data System (ADS)

    Prete, James John

    1999-12-01

    The studies proposed were designed to investigate the relationship between transperineal permanent prostate implant quality, as modeled by the radiobiologicalquantifier of implant quality, tumor control probability (TCP), and treatment efficacy, as measured by prostatespecific antigen (PSA) failure free survival. It was hypothesized that TCP could be useful in identifying which patients, or group of patients, might be at an increased risk for treatment failure among patients receiving 125I transperineal permanent prostate brachytherapy (TPPB) as the sole modality of treatment for early or intermediate stage prostatic carcinoma. The formal statement of hypothesis was that the linear- quadratic tumor control probability model for monotherapeutic 125I transperineal permanent prostate brahytherapy correlates with prostate- specific antigen failure free survival. The specific aims were: [i]to implement the TCP model in a computerized treatment planning system for TPPB, using the recently recommended dose calculation formalism and benchmark data presented in AAPM TG43 and validate it, [ii]to compute and examine the relationship between TCP and PSA failure free survival for patients receiving monotherapeutic 125I TPPB, [iii]to investigate the influence of the definition of PSA failure on the relationship between TCP and PSA failure free survival rates, and [iv]to develop a method for improving the TCP model. The conclusions were: [i]the model as implemented using AAPM TG43 formalism, produced results which were similar to that calculated by the original model. TCP was demonstrated to correlate strongly and similarly with underdosed prostate volume in comparison to data published from the original model, [ii]an analysis of 125I implants demonstrated that patients stratified into the high TCP group had PSA failure free survival rates which were superior to the rates for patients in the low TCP group, regardless of which of the five definitions of PSA failure was applied to

  6. Influence of administered indigenous microorganisms on uptake of (iodine-125). gamma. -globulin in vivo by intestinal segments of neonatal calves

    SciTech Connect

    James, R.E.; Polan, C.E.; Cummins, K.A.

    1981-01-01

    Ten calves less than 14 h of age (average 8.6 h) were anaesthetized, and the intestine was ligated into segments 10 cm in length at 3-cm intervals beginning 1.8 m anterior to the ileocecal junction and proceeding proximally. Seven treatments were assigned in random order to segments in three successive sections of the small intestine. Segments received 1 ml of viable bacteria of intestinal origin, autoclaved bacteria of intestinal origin, or sterile microbiological broth at zero time; then after 4 h they were injected with iodine-125 labeled ..gamma..-globulin. After an additional 1.5 h, the experiment was ended and uptake assayed. Two treatments measured anaerobic microbial growth after 4 h incubation with 1 ml of either sterile broth or live bacteria culture. Residual (iodine-125) ..gamma..-globulin was measured in segments receiving 1 ml of sterile broth or live bacteria culture with 5.5-h incubation followed by 15-s exposure to labeled ..gamma..-globulin. Uptake was lowest in segments receiving live bacteria as compared to segments receiving sterile inocula. Number of bacteria per gram of tissue was correlated negatively with uptake. Low corticosteroids in serum were associated with low uptake of ..gamma..-globulin.

  7. Greater Biopsy Core Number Is Associated With Improved Biochemical Control in Patients Treated With Permanent Prostate Brachytherapy

    SciTech Connect

    Bittner, Nathan; Wallner, Kent E.

    2010-11-15

    Purpose: Standard prostate biopsy schemes underestimate Gleason score in a significant percentage of cases. Extended biopsy improves diagnostic accuracy and provides more reliable prognostic information. In this study, we tested the hypothesis that greater biopsy core number should result in improved treatment outcome through better tailoring of therapy. Methods and Materials: From April 1995 to May 2006, 1,613 prostate cancer patients were treated with permanent brachytherapy. Patients were divided into five groups stratified by the number of prostate biopsy cores ({<=}6, 7-9, 10-12, 13-20, and >20 cores). Biochemical progression-free survival (bPFS), cause-specific survival (CSS), and overall survival (OS) were evaluated as a function of core number. Results: The median patient age was 66 years, and the median preimplant prostate-specific antigen was 6.5 ng/mL. The overall 10-year bPFS, CSS, and OS were 95.6%, 98.3%, and 78.6%, respectively. When bPFS was analyzed as a function of core number, the 10-year bPFS for patients with >20, 13-20, 10-12, 7-9 and {<=}6 cores was 100%, 100%, 98.3%, 95.8%, and 93.0% (p < 0.001), respectively. When evaluated by treatment era (1995-2000 vs. 2001-2006), the number of biopsy cores remained a statistically significant predictor of bPFS. On multivariate analysis, the number of biopsy cores was predictive of bPFS but did not predict for CSS or OS. Conclusion: Greater biopsy core number was associated with a statistically significant improvement in bPFS. Comprehensive regional sampling of the prostate may enhance diagnostic accuracy compared to a standard biopsy scheme, resulting in better tailoring of therapy.

  8. A comparative study of radical prostatectomy and permanent seed brachytherapy for low- and intermediate-risk prostate cancer

    PubMed Central

    Taussky, Daniel; Ouellet, Véronique; Delouya, Guila; Saad, Fred

    2016-01-01

    Introduction: We sought to compare the outcomes between radical prostatectomy (RP) and permanent seed prostate brachytherapy (PB) in patients with low- and low-intermediate-risk prostate cancer from a single tertiary care centre. Methods: Patients were selected from our institute’s internal database based on preoperative selection criteria from the National Comprehensive Cancer Network (NCCN) guidelines (2015) for low- and intermediate-risk patients. No patient had received any neo-adjuvant androgen-deprivation therapy. The endpoint was biochemical recurrence (BCR) or any salvage treatment for both RP and PB at 48 ± 4 months after treatment. The biochemical relapse threshold was set at prostate-specific antigen (PSA) ≥0.5 ng/mL for PB and two PSA values of ≥0.2 ng/mL for RP. Patients from both treatment groups were compared using non-parametric tests. A binary logistic regression analysis was performed to determine an association of treatment and pretreatment factors with a BCR at 48 months. Results: A total of 575 patients were included in this study; 254 were treated with RP and 321 with PB. BCR was not different between both groups (p=0.84, Chi-square test), and occurred in 21.2% of patients treated with RP and in 20.6% with PB. Based on univariate and multivariate logistic regression analyses, younger age, higher percentage of positive biopsies, and initial PSA were predictive of BCR. Treatment modality was not predictive in either univariate (odds ratio [OR] 0.96, 95% confidence interval [CI] 0.64–1.44; p=0.84) or multivariate (OR 1.43, 95% CI 0.89–2.30; p=0.14) analyses. Conclusions: Using closely related cutoff values for BCR, both RP and PB did not have significantly different outcomes at four years post-treatment. A longer followup may be necessary to detect a difference between treatments. PMID:27878044

  9. Multi-Parametric MRI-Directed Focal Salvage Permanent Interstitial Brachytherapy for Locally Recurrent Adenocarcinoma of the Prostate: A Novel Approach

    PubMed Central

    Wallace, T.; Avital, I.; Stojadinovic, A.; Brücher, B.L.D.M.; Cote, E.; Yu, J.

    2013-01-01

    Even with the technological advances of dose-escalated IMRT with the addition of the latest image guidance technologies, local failures still occur. The combination of MRI-based imaging techniques can yield quantitative information that reflects on the biological properties of prostatic tissues. These techniques provide unique information that can be used for tumor detection in the treated gland. With the advent of these improved imaging modalities, it has become possible to more effectively image local recurrences within the prostate gland. With better imaging, these focal recurrences can be differentially targeted with salvage brachytherapy minimizing rectal and bladder toxicity. Here we report a novel use of MRI-directed focal brachytherapy after local recurrence. This technique offers a unique opportunity to safely and successfully treat recurrent prostate cancer, previously treated with definitive radiation therapy. The use of multi-parametric MRI-directed focal salvage permanent interstitial brachytherapy for locally recurrent adenocarcinoma of the prostate is a promising strategy to avoid more aggressive and expensive treatments that are associated with increased morbidity, potentially improving survival at potentially lower costs. PMID:23412660

  10. Photon counting readout pixel array in 0.18-μm CMOS technology for on-line gamma-ray imaging of 103palladium seeds for permanent breast seed implant (PBSI) brachytherapy

    NASA Astrophysics Data System (ADS)

    Goldan, A. H.; Karim, K. S.; Reznik, A.; Caldwell, C. B.; Rowlands, J. A.

    2008-03-01

    Permanent breast seed implant (PBSI) brachytherapy technique was recently introduced as an alternative to high dose rate (HDR) brachytherapy and involves the permanent implantation of radioactive 103Palladium seeds into the surgical cavity of the breast for cancer treatment. To enable accurate seed implantation, this research introduces a gamma camera based on a hybrid amorphous selenium detector and CMOS readout pixel architecture for real-time imaging of 103Palladium seeds during the PBSI procedure. A prototype chip was designed and fabricated in 0.18-μm n-well CMOS process. We present the experimental results obtained from this integrated photon counting readout pixel.

  11. Local Control Following Permanent Prostate Brachytherapy: Effect of High Biologically Effective Dose on Biopsy Results and Oncologic Outcomes

    SciTech Connect

    Stone, Nelson N.; Stock, Richard G.; Cesaretti, Jamie A.; Unger, Pam

    2010-02-01

    Purpose: To determine factors that influence local control and systemic relapse in patients undergoing permanent prostate brachytherapy (PPB). Methods and Materials: A total of 584 patients receiving PPB alone or PPB with external beam radiation therapy (19.5%) agreed to undergo prostate biopsy (PB) at 2 years postimplantion and yearly if results were positive or if the prostate-specific antigen (PSA) level increased. Short-term hormone therapy was used with 280 (47.9%) patients. Radiation doses were converted to biologically effective doses (BED) (using alpha/beta = 2). Comparisons were made by chi-square analysis and linear regression. Survival was determined by the Kaplan-Meier method. Results: The median PSA concentration was 7.1 ng/ml, and the median follow-up period was 7.1 years. PB results were positive for 48/584 (8.2%) patients. Positive biopsy results by BED group were as follows: 22/121 (18.2%) patients received a BED of <=150 Gy; 15/244 (6.1%) patients received >150 to 200 Gy; and 6/193 (3.1%; p < 0.001) patients received >200 Gy. Significant associations of positive PB results by risk group were low-risk group BED (p = 0.019), intermediate-risk group hormone therapy (p = 0.011) and BED (p = 0.040), and high-risk group BED (p = 0.004). Biochemical freedom from failure rate at 7 years was 82.7%. Biochemical freedom from failure rate by PB result was 84.7% for negative results vs. 59.2% for positive results (p < 0.001). Cox regression analysis revealed significant associations with BED (p = 0.038) and PB results (p = 0.002) in low-risk patients, with BED (p = 0.003) in intermediate-risk patients, and with Gleason score (p = 0.006), PSA level (p < 0.001), and PB result (p = 0.038) in high-risk patients. Fifty-three (9.1%) patients died, of which eight deaths were due to prostate cancer. Cause-specific survival was 99.2% for negative PB results vs. 87.6% for positive PB results (p < 0.001). Conclusions: Higher radiation doses are required to achieve local

  12. High-Risk Prostate Cancer With Gleason Score 8-10 and PSA Level {<=}15 ng/ mL Treated With Permanent Interstitial Brachytherapy

    SciTech Connect

    Fang, L. Christine; Merrick, Gregory S.; Butler, Wayne M.; Galbreath, Robert W.; Murray, Brian C.; Reed, Joshua L.; Adamovich, Edward; Wallner, Kent E.

    2011-11-15

    Purpose: With widespread prostate-specific antigen (PSA) screening, there has been an increase in men diagnosed with high-risk prostate cancer defined by a Gleason score (GS) {>=}8 coupled with a relatively low PSA level. The optimal management of these patients has not been defined. Cause-specific survival (CSS), biochemical progression-free survival (bPFS), and overall survival (OS) were evaluated in brachytherapy patients with a GS {>=}8 and a PSA level {<=}15 ng/mL with or without androgen-deprivation therapy (ADT). Methods and Materials: From April 1995 to October 2005, 174 patients with GS {>=}8 and a PSA level {<=}15 ng/mL underwent permanent interstitial brachytherapy. Of the patients, 159 (91%) received supplemental external beam radiation, and 113 (64.9%) received ADT. The median follow-up was 6.6 years. The median postimplant Day 0 minimum percentage of the dose covering 90% of the target volume was 121.1% of prescription dose. Biochemical control was defined as a PSA level {<=}0.40 ng/mL after nadir. Multiple parameters were evaluated for impact on survival. Results: Ten-year outcomes for patients without and with ADT were 95.2% and 92.5%, respectively, for CSS (p = 0.562); 86.5% and 92.6%, respectively, for bPFS (p = 0.204); and 75.2% and 66.0%, respectively, for OS (p = 0.179). The median post-treatment PSA level for biochemically controlled patients was <0.02 ng/mL. Multivariate analysis failed to identify any predictors for CSS, whereas bPFS and OS were most closely related to patient age. Conclusions: Patients with GS {>=}8 and PSA level {<=}15 ng/mL have excellent bPFS and CSS after brachytherapy with supplemental external beam radiotherapy. The use of ADT did not significantly impact bPFS, CSS, or OS.

  13. Implanting iodine-125 seeds into rat dorsal root ganglion for neuropathic pain: neuronal microdamage without impacting hind limb motion.

    PubMed

    Jiao, Ling; Zhang, Tengda; Wang, Huixing; Zhang, Wenyi; Fan, Saijun; Huo, Xiaodong; Zheng, Baosen; Ma, Wenting

    2014-06-15

    The use of iodine-125 ((125)I) in cancer treatment has been shown to relieve patients' pain. Considering dorsal root ganglia are critical for neural transmission between the peripheral and central nervous systems, we assumed that (125)I could be implanted into rat dorsal root ganglia to provide relief for neuropathic pain. (125)I seeds with different radioactivity (0, 14.8, 29.6 MBq) were implanted separately through L4-5 and L5-6 intervertebral foramen into the vicinity of the L5 dorsal root ganglion. von Frey hair results demonstrated the mechanical pain threshold was elevated after implanting (125)I seeds from the high radioactivity group. Transmission electron microscopy revealed that nuclear membrane shrinkage, nucleolar margination, widespread mitochondrial swelling, partial vacuolization, lysosome increase, and partial endoplasmic reticulum dilation were visible at 1,440 hours in the low radioactivity group and at 336 hours in the high radioactivity group. Abundant nuclear membrane shrinkage, partial fuzzy nuclear membrane and endoplasmic reticulum necrosis were observed at 1,440 hours in the high radioactivity group. No significant difference in combined behavioral scores was detected between preoperation and postoperation in the low and high radioactivity groups. These results suggested that the mechanical pain threshold was elevated after implanting (125)I seeds without influencing motor functions of the hind limb, although cell injury was present.

  14. Androgen-deprivation therapy does not impact cause-specific or overall survival after permanent prostate brachytherapy

    SciTech Connect

    Merrick, Gregory S. . E-mail: gmerrick@wheelinghospital.com; Butler, Wayne M.; Wallner, Kent E.; Galbreath, Robert W.; Allen, Zachariah A. M.S.; Adamovich, Edward

    2006-07-01

    Purpose: To determine if androgen-deprivation therapy (ADT) has an impact on cause-specific, biochemical progression-free, or overall survival after prostate brachytherapy. Methods and Materials: From April 1995 through June 2002, 938 consecutive patients underwent brachytherapy for clinical Stage T1b to T3a (2002 AJCC) prostate cancer. All patients underwent brachytherapy more than 3 years before analysis. A total of 382 patients (40.7%) received ADT with a duration of 6 months or less in 277 and more than 6 months in 105. The median follow-up was 5.4 years. Multiple clinical, treatment, and dosimetric parameters were evaluated as predictors of cause-specific, biochemical progression-free, and overall survival. Results: The 10-year cause-specific, biochemical progression-free, and overall survival rates for the entire cohort were 96.4%, 95.9%, and 78.1%, respectively. Except for biochemical progression-free survival in high-risk patients, ADT did not statistically impact any of the three survival categories. A Cox linear-regression analysis demonstrated that Gleason score was the best predictor of cause-specific survival, whereas percent-positive biopsies, prostate volume, and risk group predicted for biochemical progression-free survival. Patient age and tobacco use were the strongest predictors of overall survival. One hundred two patients have died, with 80 of the deaths a result of cardiovascular disease (54) and second malignancies (26). To date, only 12 patients have died of metastatic prostate cancer. Conclusions: After brachytherapy, androgen-deprivation therapy did not have an impact on cause-specific or overall survival for any risk group; however, ADT had a beneficial effect on biochemical progression-free survival in high-risk patients. Cardiovascular disease and second malignancies far outweighed prostate cancer as competing causes of death.

  15. Development of virtual patient models for permanent implant brachytherapy Monte Carlo dose calculations: interdependence of CT image artifact mitigation and tissue assignment

    NASA Astrophysics Data System (ADS)

    Miksys, N.; Xu, C.; Beaulieu, L.; Thomson, R. M.

    2015-08-01

    This work investigates and compares CT image metallic artifact reduction (MAR) methods and tissue assignment schemes (TAS) for the development of virtual patient models for permanent implant brachytherapy Monte Carlo (MC) dose calculations. Four MAR techniques are investigated to mitigate seed artifacts from post-implant CT images of a homogeneous phantom and eight prostate patients: a raw sinogram approach using the original CT scanner data and three methods (simple threshold replacement (STR), 3D median filter, and virtual sinogram) requiring only the reconstructed CT image. Virtual patient models are developed using six TAS ranging from the AAPM-ESTRO-ABG TG-186 basic approach of assigning uniform density tissues (resulting in a model not dependent on MAR) to more complex models assigning prostate, calcification, and mixtures of prostate and calcification using CT-derived densities. The EGSnrc user-code BrachyDose is employed to calculate dose distributions. All four MAR methods eliminate bright seed spot artifacts, and the image-based methods provide comparable mitigation of artifacts compared with the raw sinogram approach. However, each MAR technique has limitations: STR is unable to mitigate low CT number artifacts, the median filter blurs the image which challenges the preservation of tissue heterogeneities, and both sinogram approaches introduce new streaks. Large local dose differences are generally due to differences in voxel tissue-type rather than mass density. The largest differences in target dose metrics (D90, V100, V150), over 50% lower compared to the other models, are when uncorrected CT images are used with TAS that consider calcifications. Metrics found using models which include calcifications are generally a few percent lower than prostate-only models. Generally, metrics from any MAR method and any TAS which considers calcifications agree within 6%. Overall, the studied MAR methods and TAS show promise for further retrospective MC dose

  16. Radio-guided occult lesion localisation using iodine 125 Seeds “ROLLIS” to guide surgical removal of an impalpable posterior chest wall melanoma metastasis

    SciTech Connect

    Dissanayake, Shashini; Dissanayake, Deepthi; Taylor, Donna B

    2015-09-15

    Cancer screening and surveillance programmes and the use of sophisticated imaging tools such as positron emission tomography-computed tomography (PET-CT) have increased the detection of impalpable lesions requiring imaging guidance for excision. A new technique involves intra-lesional insertion of a low-activity iodine-125 ({sup 125}I) seed and detection of the radioactive signal in theatre using a hand-held gamma probe to guide surgery. Whilst several studies describe using this method to guide the removal of impalpable breast lesions, only a handful of publications report its use to guide excision of lesions outside the breast. We describe a case in which radio-guided occult lesion localisation using an iodine 125 seed was used to guide excision of an impalpable posterior chest wall metastasis detected on PET-CT.

  17. In vivo imaging of insulin receptors by PET: preclinical evaluation of iodine-125 and iodine-124 labelled human insulin.

    PubMed

    Iozzo, P; Osman, S; Glaser, M; Knickmeier, M; Ferrannini, E; Pike, V W; Camici, P G; Law, M P

    2002-01-01

    [A(14)-*I]iodoinsulin was prepared for studies to assess the suitability of labeled iodoinsulin for positron emission tomography (PET). Iodine-125 was used to establish the methods and for preliminary studies in rats. Further studies and PET scanning in rats were carried out using iodine-124. Tissue and plasma radioactivity was measured as the uptake index (UI = [cpm x (g tissue)(-1)]/[cpm injected x (g body weight)(-1)]) at 1 to 40 min after intravenous injection of either [A(14)-(125)I]iodoinsulin or [A(14)-(124)I]iodoinsulin. For both radiotracers, initial clearance of radioactivity from plasma was rapid (T(1/2) approximately 1 min), reaching a plateau (UI = 2.8) at approximately 5 min which was maintained for 35 min. Tissue biodistributions of the two radiotracers were comparable; at 10 min after injection, UI for myocardium was 2.4, liver, 4.0, pancreas, 5.4, brain, 0.17, kidney, 22, lung, 2.3, muscle, 0.54 and fat, 0.28. Predosing rats with unlabelled insulin reduced the UI for myocardium (0.95), liver (1.8), pancreas (1.2) and brain (0.08), increased that for kidney (61) but had no effect on that for lung (2.5), muscle (0.50) or fat (0.34). Analysis of radioactivity in plasma demonstrated a decrease of [(125)I]iodoinsulin associated with the appearance of labeled metabolites; the percentage of plasma radioactivity due to [(125)I]iodoinsulin was 40% at 5 min and 10% at 10 min. The heart, liver and kidneys were visualized using [(124)I]iodoinsulin with PET.

  18. Simultaneous technetium-99 MAG(3), iodine-131-orthoiodohippurate and iodine-125 iothalamate clearance and biodistribution after bolus injection in rats.

    PubMed

    Casadevall, G; Turull, A; Piera, C; Queralt, J

    2000-07-01

    A bolus injection multiple blood sampling method was developed for the simultaneous measurement of blood and plasma clearance of three radiopharmaceuticals in rats. Technetium-99m mercaptoacetyltriglycine ([(99m)Tc]MAG(3)) and iodine-131-orthoiodohippurate ([(131)I]OIH) were used as makers of effective renal blood flow (ERBF), and iodine-125 iothalamate ([(125)I]IOT) was used as a marker of glomerular filtration rate (GFR). These methods can be easily performed in rats without arterial catheterization. Tissue biodistribution was studied in four groups of rats subjected to the following: group A, renal pedicle isolation (sham-operated); group B, ligature of one kidney pedicle; group C, ligature of both renal pedicles; and group D, ligature of both kidney pedicles and the bile duct. Renal clearance of [(99m)Tc]MAG(3) was greater than [(131)I]OIH and both agents were cleared faster than ([(125)I]-IOT). Either of the two markers of ERBF may be used in experimental studies, but it should be borne in mind that these are relative measurements of kidney performance. [(99m)Tc]MAG(3) and [(125)I]-IOT showed bile excretion in healthy rats, so they cannot completely fulfill the requirements for use as markers of ERBF. When renal function was impaired experimentally, [(99m)Tc]MAG(3) and [(125)I]-IOT were excreted in bile and [(131)I]OIH was secreted in the intestine. Thus, while the markers of ERBF and GFR may be reliable under normal physiological conditions, they may give progressively more erroneous values as renal function deteriorates.

  19. Uveal Melanoma Treated with Iodine-125 Episcleral Plaque: An Analysis of Dose on Disease Control and Visual Outcomes

    PubMed Central

    Perez, Bradford A.; Mettu, Pradeep; Vajzovic, Lejla; Rivera, Douglas; Alkaissi, Ali; Steffey, Beverly A.; Cai, Jing; Stinnett, Sandra; Dutton, Jonathan J.; Buckley, Edward G.; Halperin, Edward; Marks, Lawrence B.; Mruthyunjaya, Prithvi; Kirsch, David G.

    2014-01-01

    PURPOSE In the treatment of uveal melanomas, the optimal prescribed dose to maximize disease control, but minimize radiation-related complications is unknown. Historically our institution has treated uveal melanomas to doses less than 85 Gy to the tumor apex even if the apex was less than 5mm in height. Here, we investigate how tumor control and visual outcomes are affected by the radiation dose at the tumor apex. METHODS AND MATERIALS A retrospective review was performed to evaluate patients treated for uveal melanoma with Iodine-125 plaques between 1988 and 2010. Radiation dose is reported as dose to tumor apex and dose to 5 mm. Primary end points included time to local failure, distant failure, and death. Secondary end points included eye preservation, visual acuity, and radiation-related complications. Univariate and multivariate analyses were performed to determine association between radiation dose and the end point variables. RESULTS One hundred ninety patients with sufficient data to evaluate the end points were included. The 5 year local control (LC) rate was 91%. The 5 year distant metastases (DM) rate was 10%. The 5 year overall survival (OS) rate was 84%. There were no differences in outcome (LC, DM, OS) when dose was stratified by apex dose quartile (<69 Gy, 69–81 Gy, 81–89 Gy, >89 Gy). However, increasing apex dose and dose to 5 mm depth were correlated with greater visual acuity loss (p=0.02, p=0.0006), worse final visual acuity (p=0.02, p<0.0001) and radiation complications (p<0.0001, p=0.0009). In addition, enucleation rates were worse with increasing quartiles of dose to 5 mm (p=0.0001). CONCLUSIONS Doses at least as low as 69 Gy prescribed to the tumor apex achieve rates of local control, distant metastasis free survival, and overall survival that are similar to radiation doses of 85 Gy to the tumor apex, but with improved visual outcomes. PMID:24613808

  20. A radiobiology-based inverse treatment planning method for optimisation of permanent l-125 prostate implants in focal brachytherapy

    NASA Astrophysics Data System (ADS)

    Haworth, Annette; Mears, Christopher; Betts, John M.; Reynolds, Hayley M.; Tack, Guido; Leo, Kevin; Williams, Scott; Ebert, Martin A.

    2016-01-01

    Treatment plans for ten patients, initially treated with a conventional approach to low dose-rate brachytherapy (LDR, 145 Gy to entire prostate), were compared with plans for the same patients created with an inverse-optimisation planning process utilising a biologically-based objective. The ‘biological optimisation’ considered a non-uniform distribution of tumour cell density through the prostate based on known and expected locations of the tumour. Using dose planning-objectives derived from our previous biological-model validation study, the volume of the urethra receiving 125% of the conventional prescription (145 Gy) was reduced from a median value of 64% to less than 8% whilst maintaining high values of TCP. On average, the number of planned seeds was reduced from 85 to less than 75. The robustness of plans to random seed displacements needs to be carefully considered when using contemporary seed placement techniques. We conclude that an inverse planning approach to LDR treatments, based on a biological objective, has the potential to maintain high rates of tumour control whilst minimising dose to healthy tissue. In future, the radiobiological model will be informed using multi-parametric MRI to provide a personalised medicine approach.

  1. Feasibility of vibro-acoustography with a quasi-2D ultrasound array transducer for detection and localizing of permanent prostate brachytherapy seeds: A pilot ex vivo study

    SciTech Connect

    Mehrmohammadi, Mohammad; Kinnick, Randall R.; Fatemi, Mostafa; Alizad, Azra; Davis, Brian J.

    2014-09-15

    Purpose: Effective permanent prostate brachytherapy (PPB) requires precise placement of radioactive seeds in and around the prostate. The impetus for this research is to examine a new ultrasound-based imaging modality, vibro-acoustography (VA), which may serve to provide a high rate of PPB seed detection while also effecting enhanced prostate imaging. The authors investigate the ability of VA, implemented on a clinical ultrasound (US) scanner and equipped with a quasi-2D (Q2D) array US transducer, to detect and localize PPB seeds in excised prostate specimens. Methods: Nonradioactive brachytherapy seeds were implanted into four excised cadaver prostates. A clinical US scanner equipped with a Q2D array US transducer was customized to acquire both US and C-scan VA images at various depths. The VA images were then used to detect and localize the implanted seeds in prostate tissue. To validate the VA results, computed tomography (CT) images of the same tissue samples were obtained to serve as the reference by which to evaluate the performance of VA in PPB seed detection. Results: The results indicate that VA is capable of accurately identifying the presence and distribution of PPB seeds with a high imaging contrast. Moreover, a large ratio of the PPB seeds implanted into prostate tissue samples could be detected through acquired VA images. Using CT-based seed identification as the standard, VA was capable of detecting 74%–92% of the implanted seeds. Additionally, the angular independency of VA in detecting PPB seeds was demonstrated through a well-controlled phantom experiment. Conclusions: Q2DVA detected a substantial portion of the seeds by using a 2D array US transducer in excised prostate tissue specimens. While VA has inherent advantages associated with conventional US imaging, it has the additional advantage of permitting detection of PPB seeds independent of their orientation. These results suggest the potential of VA as a method for PPB imaging that

  2. A detailed radiobiological and dosimetric analysis of biochemical outcomes in a case-control study of permanent prostate brachytherapy patients

    SciTech Connect

    Butler, Wayne M.; Stewart, Renee R.; Merrick, Gregory S.

    2009-03-15

    the harmonic mean and expressions of the generalized EUD. In this case-control study of prostate brachytherapy biochemical failures and nonfailures, there were no radiobiological parameters derived from detailed DVH-based analysis that predicted for biochemical control. This may indicate that in our approach, implant dosimetry is at or near the limits of clinically effective dose escalation.

  3. A detailed radiobiological and dosimetric analysis of biochemical outcomes in a case-control study of permanent prostate brachytherapy patients.

    PubMed

    Butler, Wayne M; Stewart, Renee R; Merrick, Gregory S

    2009-03-01

    generalized EUD. In this case-control study of prostate brachytherapy biochemical failures and nonfailures, there were no radiobiological parameters derived from detailed DVH-based analysis that predicted for biochemical control. This may indicate that in our approach, implant dosimetry is at or near the limits of clinically effective dose escalation.

  4. Stereotactic brachytherapy of low-grade cerebral glioma after tumor resection.

    PubMed

    Suchorska, Bogdana; Ruge, Maximilian; Treuer, Harald; Sturm, Volker; Voges, Jürgen

    2011-10-01

    The purpose of this study was to assess the impact of stereotactic brachytherapy (SBT) on survival time and outcome when applied after resection of low-grade glioma (LGG) of World Health Organization grade II. From January 1982 through December 2006 we treated 1024 patients who had glioma with stereotactic implantation of iodine-125 seeds and SBT in accordance with a prospective protocol. For the present analysis, we selected 95 of 277 patients with LGG, in whom SBT was applied to treat progressive (43 patients) or recurrent (52 patients) tumor after resection. At 24 months after seed implantation, the tumor response rate was 35.9%, and the tumor control rate was 97.3%. The median progression-free-survival (PFS) duration after SBT was 52.7 ± 7.1 months. Five-year and 10-year PFS probabilities were 43.4% and 10.7%, respectively. Malignant tumor transformation, the diagnosis "astrocytoma," and tumor volume >20 mL were significantly associated with reduced PFS. Tumor progression or relapse after SBT (53 of 95 patients) was treated with tumor resection, a second SBT, chemotherapy, and/or radiotherapy. The median overall survival duration (from the first diagnosis of LGG until the patient's last contact) was 245.0 ± 4.9 months. Patients still under observation after seed implantation had a median follow-up time of 156.4 ± 55.7 months. Perioperative transient morbidity was 1.1%, and the frequency of permanent morbidity caused by SBT was 3.3%. In conclusion, SBT of recurrent or progressive LGG after resection located in functionally critical brain areas has high local efficacy and comparably low morbidity. Referred to individually adopted glioma treatment concepts SBT provides a reasonably long PFS, thus improving overall survival. In selected patients, SBT can lead to delays in the application of chemotherapy and/or radiotherapy.

  5. AAPM recommendations on dose prescription and reporting methods for permanent interstitial brachytherapy for prostate cancer: Report of Task Group 137

    SciTech Connect

    Nath, Ravinder; Bice, William S.; Butler, Wayne M.; Chen Zhe; Meigooni, Ali S.; Narayana, Vrinda; Rivard, Mark J.; Yu Yan

    2009-11-15

    During the past decade, permanent radioactive source implantation of the prostate has become the standard of care for selected prostate cancer patients, and the techniques for implantation have evolved in many different forms. Although most implants use {sup 125}I or {sup 103}Pd sources, clinical use of {sup 131}Cs sources has also recently been introduced. These sources produce different dose distributions and irradiate the tumors at different dose rates. Ultrasound was used originally to guide the planning and implantation of sources in the tumor. More recently, CT and/or MR are used routinely in many clinics for dose evaluation and planning. Several investigators reported that the tumor volumes and target volumes delineated from ultrasound, CT, and MR can vary substantially because of the inherent differences in these imaging modalities. It has also been reported that these volumes depend critically on the time of imaging after the implant. Many clinics, in particular those using intraoperative implantation, perform imaging only on the day of the implant. Because the effects of edema caused by surgical trauma can vary from one patient to another and resolve at different rates, the timing of imaging for dosimetry evaluation can have a profound effect on the dose reported (to have been delivered), i.e., for the same implant (same dose delivered), CT at different timing can yield different doses reported. Also, many different loading patterns and margins around the tumor volumes have been used, and these may lead to variations in the dose delivered. In this report, the current literature on these issues is reviewed, and the impact of these issues on the radiobiological response is estimated. The radiobiological models for the biological equivalent dose (BED) are reviewed. Starting with the BED model for acute single doses, the models for fractionated doses, continuous low-dose-rate irradiation, and both homogeneous and inhomogeneous dose distributions, as well as

  6. Comparison of Dosimetric and Biologic Effective Dose Parameters for Prostate and Urethra Using {sup 131}Cs and {sup 125}I for Prostate Permanent Implant Brachytherapy

    SciTech Connect

    Sahgal, Arjun; Jabbari, Siavash; Chen, Josephine; Pickett, Barbie; Roach, Mack; Weinberg, Vivian; Hsu, I-C.; Pouliot, Jean

    2008-09-01

    Purpose: To compare the urethral and prostate absolute and biologic effective doses (BEDs) for {sup 131}Cs and {sup 125}I prostate permanent implant brachytherapy (PPI). Methods and Materials: Eight previously implanted manually planned {sup 125}I PPI patients were replanned manually with {sup 131}Cs, and re-planned using Inverse Planning Simulated Annealing. {sup 131}Cs activity and the prescribed dose (115 Gy) were determined from that recommended by IsoRay. The BED was calculated for the prostate and urethra using an {alpha}/{beta} ratio of 2 and was also calculated for the prostate using an {alpha}/{beta} ratio of 6 and a urethral {alpha}/{beta} ratio of 2. The primary endpoints of this study were the prostate D{sub 90} BED (pD{sub 90}BED) and urethral D{sub 30} BED normalized to the maximal potential prostate D{sub 90} BED (nuD{sub 30}BED). Results: The manual plan comparison ({alpha}/{beta} = 2) yielded no significant difference in the prostate D{sub 90} BED (median, 192 Gy{sub 2} for both isotopes). No significant difference was observed for the nuD{sub 30}BED (median, 199 Gy{sub 2} and 202 Gy{sub 2} for {sup 125}I and {sup 131}Cs, respectively). For the inverse planning simulated annealing plan comparisons ({alpha}/{beta} 2), the prostate D{sub 90} BED was significantly lower with {sup 131}Cs than with {sup 125}I (median, 177 Gy{sub 2} vs. 187 Gy{sub 2}, respectively; p = 0.01). However, the nuD{sub 30}BED was significantly greater with {sup 131}Cs than with {sup 125}I (median, 192 Gy{sub 2} vs. 189 Gy{sub 2}, respectively; p = 0.01). Both the manual and the inverse planning simulated annealing plans resulted in a significantly lower prostate D{sub 90} BED (p = 0.01) and significantly greater nuD{sub 30}BED for {sup 131}Cs (p = 0.01), compared with {sup 125}I, when the prostate {alpha}/{beta} ratio was 6 and the urethral {alpha}/{beta} ratio was 2. Conclusion: This report highlights the controversy in comparing the dose to both the prostate and the organs

  7. Brachytherapy versus prostatectomy in localized prostate cancer: Results of a French multicenter prospective medico-economic study

    SciTech Connect

    Buron, Catherine; Le Vu, Beatrice; Cosset, Jean-Marc; Peiffert, Didier; Delannes, Martine; Flam, Thierry; Guerif, Stephane; Salem, Naji; Chauveinc, Laurent; Livartowski, Alain . E-mail: alain.livartowski@curie.net

    2007-03-01

    Purpose: To prospectively compare health-related quality of life (HRQOL), patient-reported treatment-related symptoms, and costs of iodine-125 permanent implant interstitial brachytherapy (IB) with those of radical prostatectomy (RP) during the first 2 years after these treatments for localized prostate cancer. Methods and Materials: A total of 435 men with localized low-risk prostate cancer, from 11 French hospitals, treated with IB (308) or RP (127), were offered to complete the European Organization for Research and Treatment of Cancer core Quality of Life Questionnaire QLQ-C30 version 3 (EORTC QLQ-C30) and the prostate cancer specific EORTC QLQ-PR25 module before and at the end of treatment, 2, 6, 12, 18, and 24 months after treatment. Repeated measures analysis of variance and analysis of covariance were conducted on HRQOL changes. Comparative cost analysis covered initial treatment, hospital follow-up, outpatient and production loss costs. Results: Just after treatment, the decrease of global HRQOL was less pronounced in the IB than in the RP group, with a 13.5 points difference (p < 0.0001). A difference slightly in favor of RP was observed 6 months after treatment (-7.5 points, p = 0.0164) and was maintained at 24 months (-8.2 points, p = 0.0379). Impotence and urinary incontinence were more pronounced after RP, whereas urinary frequency, urgency, and urination pain were more frequent after IB. Mean societal costs did not differ between IB ( Euro 8,019 at T24) and RP ( Euro 8,715 at T24, p = 0.0843) regardless of the period. Conclusions: This study suggests a similar cost profile in France for IB and RP but with different HRQOL and side effect profiles. Those findings may be used to tailor localized prostate cancer treatments to suit individual patients' needs.

  8. Plastic optical fibre sensor for in-vivo radiation monitoring during brachytherapy

    NASA Astrophysics Data System (ADS)

    Woulfe, P.; Sullivan, F. J.; Lewis, E.; O'Keeffe, S.

    2015-09-01

    An optical fibre sensor is presented for applications in real-time in-vivo monitoring of the radiation dose a cancer patient receives during seed implantation in Brachytherapy. The sensor is based on radioluminescence whereby radiation sensitive scintillation material is embedded in the core of a 1mm plastic optical fibre. Three scintillation materials are investigated: thallium-doped caesium iodide (CsI:Tl), terbium-doped gadolinium oxysulphide (Gd2O2S:Tb) and europium-doped lanthanum oxysulphide (La2O2S:Eu). Terbium-doped gadolinium oxysulphide was identified as being the most suitable scintillator and further testing demonstrates its measureable response to different activities of Iodine-125, the radio-active source commonly used in Brachytherapy for treating prostate cancer.

  9. Portal Vein Stenting Combined with Iodine-125 Seeds Endovascular Implantation Followed by Transcatheter Arterial Chemoembolization for Treatment of Hepatocellular Carcinoma Patients with Portal Vein Tumor Thrombus

    PubMed Central

    Zhou, Tanyang; Zhu, Tongyin; Zhang, Yuelin; Nie, Chunhui; Ai, Jing; Zhou, Guanhui; Zhang, Aibin; Dong, Meng-Jie; Wang, Wei-Lin

    2016-01-01

    Aim was to assess the therapeutic value of portal vein stenting (PVS) combined with iodine-125 seed (125I seed) strand endovascular implantation followed by transcatheter arterial chemoembolization (TACE) for treating patients with hepatocellular carcinoma (HCC) and portal vein tumor thrombus (PVTT). This was a retrospective study of 34 patients aged 29–81 years, diagnosed HCC with PVTT, and treated with PVS combined with 125I seed strand endovascular implantation followed by TACE between January 2012 and August 2014. Survival, stent patency, technical success rate, complications related to the procedure, and adverse events were recorded. The technical success rate was 100%. No serious procedure-related adverse event was recorded. The median survival was 147 days. The cumulative survival rates and stent patency rates at 90, 180, and 360 days were 94.1%, 61.8%, and 32.4% and 97.1% (33/34), 76.9% (24/34), and 29.4% (10/34), respectively. PVS combined with 125I seed strand endovascular implantation followed by TACE is feasible for patients with HCC and PVTT. It resulted in appropriate survival and stent patency, with no procedure-related adverse effects. PMID:27999793

  10. Dosimetry of a thyroid uptake detected in seed migration survey following a patient's iodine-125 prostate implant and in vitro measurements of intentional seed leakages

    SciTech Connect

    Chen Qinsheng; Russell, John L. Jr.; Macklis, Roger R.; Weinhous, Martin S.; Blair, Henry F.

    2006-07-15

    As a quality control procedure, a post-implant seed migration survey has been accomplished on 340 prostate cancer patients since November 2001. Pulmonary seed embolization and intracardiac seed embolization have been detected. A case of thyroid uptake due to leaking iodine-125 (I-125) sources was also seized. In order to determine the dose to the thyroid, a dosimetry method was developed to link in vivo measurements and the cumulated dose to the thyroid. The calculated source leakage half-life in the case was approximately 15 days based on the measurements and the estimated cumulated dose to thyroid was 204 cGy. It is concluded that one seed was leaking. In order to verify the in vivo measurements, intentional in vitro seed leakage tests were performed. A seed was cut open and placed in a sealed glass container filled with a given volume of saline. The I-125 concentration in the saline was subsequently measured over a period of six months. Consistent in vivo and in vitro results were obtained. Recent incidents of seed leaks reported from other centers have drawn practitioners' attention to this problem. In order to make the measurements more useful, the seed leakage tests were expanded to include I-125 seeds from six other vendors. The results show that the leakage half-lives of those seeds varied from nine days to a half-year. Two seed models demonstrated least leakage. Since the measurements lasted for six months, the escape of iodine resulted from oxidation of iodide in the saline was a concern for the measurement accuracy. As a reference, another set of leakage tests were performed by adding sodium thiosulfate salt (Na{sub 2}S{sub 2}O{sub 3}{center_dot}5H{sub 2}O) to the saline. Sodium thiosulfate is a reducing agent that prevents the conversion of iodide to iodate so as to minimize I-125 evaporation. As a result, significantly shortened leakage half-lives were observed in this group. Seed agitation was also performed and no significant deviations of the

  11. Long-term Results of the UCSF-LBNL Randomized Trial: Charged Particle With Helium Ion Versus Iodine-125 Plaque Therapy for Choroidal and Ciliary Body Melanoma

    SciTech Connect

    Mishra, Kavita K.; Quivey, Jeanne M.; Daftari, Inder K.; Weinberg, Vivian; Cole, Tia B.; Patel, Kishan; Castro, Joseph R.; Phillips, Theodore L.; Char, Devron H.

    2015-06-01

    Purpose: Relevant clinical data are needed given the increasing national interest in charged particle radiation therapy (CPT) programs. Here we report long-term outcomes from the only randomized, stratified trial comparing CPT with iodine-125 plaque therapy for choroidal and ciliary body melanoma. Methods and Materials: From 1985 to 1991, 184 patients met eligibility criteria and were randomized to receive particle (86 patients) or plaque therapy (98 patients). Patients were stratified by tumor diameter, thickness, distance to disc/fovea, anterior extension, and visual acuity. Tumors close to the optic disc were included. Local tumor control, as well as eye preservation, metastases due to melanoma, and survival were evaluated. Results: Median follow-up times for particle and plaque arm patients were 14.6 years and 12.3 years, respectively (P=.22), and for those alive at last follow-up, 18.5 and 16.5 years, respectively (P=.81). Local control (LC) for particle versus plaque treatment was 100% versus 84% at 5 years, and 98% versus 79% at 12 years, respectively (log rank: P=.0006). If patients with tumors close to the disc (<2 mm) were excluded, CPT still resulted in significantly improved LC: 100% versus 90% at 5 years and 98% versus 86% at 12 years, respectively (log rank: P=.048). Enucleation rate was lower after CPT: 11% versus 22% at 5 years and 17% versus 37% at 12 years, respectively (log rank: P=.01). Using Cox regression model, likelihood ratio test, treatment was the most important predictor of LC (P=.0002) and eye preservation (P=.01). CPT was a significant predictor of prolonged disease-free survival (log rank: P=.001). Conclusions: Particle therapy resulted in significantly improved local control, eye preservation, and disease-free survival as confirmed by long-term outcomes from the only randomized study available to date comparing radiation modalities in choroidal and ciliary body melanoma.

  12. WE-A-17A-09: Exploiting Electromagnetic Technologies for Real-Time Seed Drop Position Validation in Permanent Implant Brachytherapy

    SciTech Connect

    Racine, E; Hautvast, G; Binnekamp, D; Beaulieu, L

    2014-06-15

    Purpose: To report on preliminary results validating the performance of a specially designed LDR brachytherapy needle prototype possessing both electromagnetic (EM) tracking and seed drop detection abilities. Methods: An EM hollow needle prototype has been designed and constructed in collaboration with research partner Philips Healthcare. The needle possesses conventional 3D tracking capabilities, along with a novel seed drop detection mechanism exploiting local changes of electromagnetic properties generated by the passage of seeds in the needle's embedded sensor coils. These two capabilities are exploited by proprietary engineering and signal processing techniques to generate seed drop position estimates in real-time treatment delivery. The electromagnetic tracking system (EMTS) used for the experiment is the NDI Aurora Planar Field Generator. The experiment consisted of dropping a total of 35 seeds in a prismatic agarose phantom, and comparing the 3D seed drop positions of the EMTS to those obtained by an image analysis of subsequent micro-CT scans. Drop position error computations and statistical analysis were performed after a 3D registration of the two seed distributions. Results: Of the 35 seeds dropped in the phantom, 32 were properly detected by the needle prototype. Absolute drop position errors among the detected seeds ranged from 0.5 to 4.8 mm with mean and standard deviation values of 1.6 and 0.9 mm, respectively. Error measurements also include undesirable and uncontrollable effects such as seed motion upon deposition. The true accuracy performance of the needle prototype is therefore underestimated. Conclusion: This preliminary study demonstrates the potential benefits of EM technologies in detecting the passage of seeds in a hollow needle as a means of generating drop position estimates in real-time treatment delivery. Such tools could therefore represent a potentially interesting addition to existing brachytherapy protocols for rapid dosimetry

  13. Brachytherapy for Patients With Prostate Cancer: American Society of Clinical Oncology/Cancer Care Ontario Joint Guideline Update.

    PubMed

    Chin, Joseph; Rumble, R Bryan; Kollmeier, Marisa; Heath, Elisabeth; Efstathiou, Jason; Dorff, Tanya; Berman, Barry; Feifer, Andrew; Jacques, Arthur; Loblaw, D Andrew

    2017-03-27

    Purpose To jointly update the Cancer Care Ontario guideline on brachytherapy for patients with prostate cancer to account for new evidence. Methods An Update Panel conducted a targeted systematic literature review and identified more recent randomized controlled trials comparing dose-escalated external beam radiation therapy (EBRT) with brachytherapy in men with prostate cancer. Results Five randomized controlled trials provided the evidence for this update. Recommendations For patients with low-risk prostate cancer who require or choose active treatment, low-dose rate brachytherapy (LDR) alone, EBRT alone, and/or radical prostatectomy (RP) should be offered to eligible patients. For patients with intermediate-risk prostate cancer choosing EBRT with or without androgen-deprivation therapy, brachytherapy boost (LDR or high-dose rate [HDR]) should be offered to eligible patients. For low-intermediate risk prostate cancer (Gleason 7, prostate-specific antigen < 10 ng/mL or Gleason 6, prostate-specific antigen, 10 to 20 ng/mL), LDR brachytherapy alone may be offered as monotherapy. For patients with high-risk prostate cancer receiving EBRT and androgen-deprivation therapy, brachytherapy boost (LDR or HDR) should be offered to eligible patients. Iodine-125 and palladium-103 are each reasonable isotope options for patients receiving LDR brachytherapy; no recommendation can be made for or against using cesium-131 or HDR monotherapy. Patients should be encouraged to participate in clinical trials to test novel or targeted approaches to this disease. Additional information is available at www.asco.org/Brachytherapy-guideline and www.asco.org/guidelineswiki .

  14. Comparison of Intraoperatively Built Custom Linked Seeds Versus Loose Seed Gun Applicator Technique Using Real-Time Intraoperative Planning for Permanent Prostate Brachytherapy

    SciTech Connect

    Zauls, A. Jason; Ashenafi, Michael S.; Onicescu, Georgiana; Clarke, Harry S.; Marshall, David T.

    2011-11-15

    Purpose: To report our dosimetric results using a novel push-button seed delivery system that constructs custom links of seeds intraoperatively. Methods and Materials: From 2005 to 2007, 43 patients underwent implantation using a gun applicator (GA), and from 2007 to 2008, 48 patientsunderwent implantation with a novel technique allowing creation of intraoperatively built custom links of seeds (IBCL). Specific endpoint analyses were prostate D90% (pD90%), rV100% > 1.3 cc, and overall time under anesthesia. Results: Final analyses included 91 patients, 43 GA and 48 IBCL. Absolute change in pD90% ({Delta}pD90%) between intraoperative and postoperative plans was evaluated. Using GA method, the {Delta}pD90% was -8.1Gy and -12.8Gy for I-125 and Pd-103 implants, respectively. Similarly, the IBCL technique resulted in a {Delta}pD90% of -8.7Gy and -9.8Gy for I-125 and Pd-103 implants, respectively. No statistically significant difference in {Delta}pD90% was found comparing methods. The GA method had two intraoperative and 10 postoperative rV100% >1.3 cc. For IBCL, five intraoperative and eight postoperative plans had rV100% >1.3 cc. For GA, the mean time under anesthesia was 75 min and 87 min for Pd-103 and I-125 implants, respectively. For IBCL, the mean time was 86 and 98 min for Pd-103 and I-125. There was a statistical difference between the methods when comparing mean time under anesthesia. Conclusions: Dosimetrically relevant endpoints were equivalent between the two methods. Currently, time under anesthesia is longer using the IBCL technique but has decreased over time. IBCL is a straightforward brachytherapy technique that can be implemented into clinical practice as an alternative to gun applicators.

  15. 10-Year Experience With I-125 Prostate Brachytherapy at the Princess Margaret Hospital: Results for 1,100 Patients

    SciTech Connect

    Crook, Juanita; Borg, Jette; Evans, Andrew; Toi, Ants; Saibishkumar, E.P.; Fung, Sharon; Ma, Clement

    2011-08-01

    Purpose: To report outcomes for 1,111 men treated with iodine-125 brachytherapy (BT) at a single institution. Methods and Materials: A total of 1,111 men (median age, 63) were treated with iodine-125 prostate BT for low- or intermediate-risk prostate cancer between March 1999 and November 2008. Median prostate-specific antigen (PSA) level was 5.4 ng/ml (range, 0.9-26.1). T stage was T1c in 66% and T2 in 34% of patients. Gleason score was 6 in 90.1% and 7 or 8 in 9.9% of patients. Neoadjuvant hormonal therapy (2-6 months course) was used in 10.1% of patients and combined external radiotherapy (45 Gy) with BT (110 Gy) in 4.1% (n = 46) of patients. Univariate and multivariate Cox proportional hazards were used to determine predictors of failure. Results: Median follow-up was 42 months (range, 6-114), but for biochemical freedom from relapse, a minimum PSA test follow-up of 30 months was required (median 54; n = 776). There were 27 failures, yielding an actuarial 7-year disease-free survival rate of 95.2% (96 at risk beyond 84 months). All failures underwent repeat 12-core transrectal ultrasound -guided biopsies, confirming 8 local failures. On multivariate analysis, Gleason score was the only independent predictor of failure (p = 0.001; hazard ratio, 4.8 (1.9-12.4). Median International Prostate Symptom score from 12 to 108 months ranged between 3 and 9. Of the men reporting baseline potency, 82.8% retained satisfactory erectile function beyond 5 years. Conclusion: Iodine-125 prostate BT is a highly effective treatment option for favorable- and intermediate-risk prostate cancer and is associated with maintenance of good urinary and erectile functions.

  16. Dosimetric characteristics of the new RadioCoil{sup TM} {sup 103}Pd wire line source for use in permanent brachytherapy implants

    SciTech Connect

    Meigooni, A.S.; Zhang, H.; Clark, J.R.; Rachabatthula, V.; Koona, R.A.

    2004-11-01

    Recently, a novel linear brachytherapy source in the form of a coiled wire has become available for use in interstitial implants of various treatment sites such as prostate gland. This source type employs a design completely different from that of most 'seed' sources currently on the market, one which improves upon or eliminates several common problems with such sources. Dosimetric characteristics of these sources with active lengths 0.5 cm to 5.0 cm were determined for clinical application. For 0.5 cm and 1.0 cm active length sources, the dose rate constant, radial dose function, and two-dimensional (2D) anisotropy function were experimentally and theoretically determined following the updated AAPM Task Group 43 (TG-43U1) recommendations. Radial dose functions and/or 'along-away' matrix functions were also obtained for sources with active lengths 2.0 cm to 5.0 cm. Measurements were performed with LiF thermoluminescent dosimeters in Solid Water{sup TM} phantoms. Measured data was compared to Monte Carlo simulated data in Solid Water{sup TM} utilizing the PTRAN code, version 7.43. After finding the data to be in agreement, Monte Carlo calculations were performed in liquid water to obtain clinically applicable dosimetric data as per TG-43U1 recommendations. The results indicated the dose rate constant of the 0.5 cm long RadioCoil{sup TM103}Pd source in Solid Water{sup TM} to be 0.641 cGy h{sup -1} U{sup -1} when measured, and 0.636 cGy h{sup -1} U{sup -1} when simulated by Monte Carlo. The calculated dose rate constant in liquid water was found to be 0.650 cGy h{sup -1} U{sup -1}. These values are comparable to other commercially available sources. Complete dosimetric data and simulation results are described in this paper. Per TG-43U1, clinical treatment planning systems should utilize the values reported for liquid water.

  17. Optical fibre luminescence sensor for real-time LDR brachytherapy dosimetry

    NASA Astrophysics Data System (ADS)

    Woulfe, P.; Sullivan, F. J.; O'Keeffe, S.

    2016-05-01

    An optical fibre sensor for monitoring low dose radiation is presented. The sensor is based on a scintillation material embedded within the optical fibre core, which emits visible light when exposed to low level ionising radiation. The incident level of ionising radiation can be determined by analysing the optical emission. An optical fibre sensor is presented, based on radioluminescence whereby radiation sensitive scintillation material, terbium doped gadolinium oxysulphide (Gd2O2S:Tb), is embedded in a cavity of 250μm of a 500μm plastic optical fibre. The sensor is designed for in-vivo monitoring of the radiation dose during radio-active seed implantation for brachytherapy, in prostate cancer treatment, providing oncologists with real-time information of the radiation dose to the target area and/or nearby critical structures. The radiation from the brachytherapy seeds causes emission of visible light from the scintillation material through the process of radioluminescence, which penetrates the fibre, propagating along the optical fibre for remote detection using a multi-pixel photon counter. The sensor demonstrates a high sensitivity to Iodine-125, the radioactive source most commonly used in brachytherapy for treating prostate cancer.

  18. Evaluation of (iodine-125)N,N,N'-trimethyl-N'-(2-hydroxy-3-methyl-5-iodobenzyl)-1,3- propanediamine lung uptake using an isolated-perfused lung model

    SciTech Connect

    Slosman, D.O.; Brill, A.B.; Polla, B.S.; Alderson, P.O.

    1987-02-01

    Lung uptake of N,N,N'-trimethyl-N'-(2-Hydroxy-3-methyl-5-iodobenzyl)-1,3- propanediamine (HIPDM) has been reported, but the mechanism of this process has not yet been established. Thus, single-pass (/sup 125/I)HIPDM accumulation was studied in rat lungs perfused with a Krebs-Ringer bicarbonate buffer containing 4.5% bovine albumin. Iodine-125 HIPDM lung accumulation was monitored by the percent of extraction per gram of lung tissue. Iodine-125 HIPDM lung uptake did not appear to occur by simple diffusion. As the time of perfusion was increased from 2 to 15 min, the rate of uptake of 2 microM (/sup 125/I)HIPDM decreased by 40%. During a 2-min perfusion, 98.6% +/- 6.7 (n = 8) extraction was observed with 2 microM (/sup 125/I)HIPDM, but only 38% +/- 2.0 (n = 3) was extracted when the (/sup 125/I)HIPDM concentration was 1 mM. The addition of 1 mM chlorpromazine, propranolol or imipramine also decreased (/sup 125/I)HIPDM lung uptake to 43.0% +/- 1.5, 51.4% +/- 2.2, and 49.8% +/- 0.8, respectively, (each n = 4 - 6, p less than 0.001). Cold (4 degrees C) had little effect on pulmonary accumulation (77.7% +/- 7.4, n = 5, p less than 0.01), and the addition of ouabain or the use of sodium-free medium had no effect. Thus, pulmonary (/sup 125/I)HIPDM accumulation does not appear to occur by sodium-dependent active transport. Rather, its uptake appears to be similar to the uptake of other basic amines, such as propranolol and imipramine, which are known to bind by physico-chemical interactions to pulmonary endothelial cell membranes and reflect pulmonary vascular surface area.

  19. [Prostate cancer brachytherapy].

    PubMed

    Pommier, P; Guérif, S; Peiffert, D; Créhange, G; Hannoun-Lévi, J-M; de Crevoisier, R

    2016-09-01

    Prostate brachytherapy techniques are described, concerning both Iodine 125 high dose rate brachytherapy. The following parts are presented: brachytherapy indications, technical description, immediate postoperative management and post-treatment evaluation, and 4 to 6 weeks as well as long-term follow-up.

  20. Equivalent Biochemical Control and Improved Prostate-Specific Antigen Nadir After Permanent Prostate Seed Implant Brachytherapy Versus High-Dose Three-Dimensional Conformal Radiotherapy and High-Dose Conformal Proton Beam Radiotherapy Boost

    SciTech Connect

    Jabbari, Siavash; Weinberg, Vivian K.; Shinohara, Katsuto; Speight, Joycelyn L.; Gottschalk, Alexander R.; Hsu, I.-C.; Pickett, Barby; McLaughlin, Patrick W.; Sandler, Howard M.; Roach, Mack

    2010-01-15

    Purpose: Permanent prostate implant brachytherapy (PPI), three-dimensional conformal radiotherapy (3D-CRT), and conformal proton beam radiotherapy (CPBRT) are used in the treatment of localized prostate cancer, although no head-to-head trials have compared these modalities. We studied the biochemical control (biochemical no evidence of disease [bNED]) and prostate-specific antigen (PSA) nadir achieved with contemporary PPI, and evaluated it against 3D-CRT and CPBRT. Patients and Methods: A total of 249 patients were treated with PPI at the University of California, San Francisco, and the outcomes were compared with those from a 3D-CRT cohort and the published results of a high-dose CPBRT boost (CPBRTB) trial. For each comparison, subsets of the PPI cohort were selected with patient and disease criteria similar to those of the reference group. Results: With a median follow-up of 5.3 years, the bNED rate at 5 and 7 years achieved with PPI was 92% and 86%, respectively, using the American Society for Therapeutic Radiology and Oncology (ASTRO) definition, and 93% using the PSA nadir plus 2 ng/mL definition. Using the ASTRO definition, a 5-year bNED rate of 78% was achieved for the 3D-CRT patients compared with 94% for a comparable PPI subset and 93% vs. 92%, respectively, using the PSA nadir plus 2 ng/mL definition. The median PSA nadir for patients treated with PPI and 3D-CRT was 0.10 and 0.40 ng/mL, respectively (p < .0001). For the CPBRT comparison, the 5-year bNED rate after a CPBRTB was 91% using the ASTRO definition vs. 93% for a similar group of PPI patients. A greater proportion of PPI patients achieved a lower PSA nadir compared with those achieved in the CPBRTB trial (PSA nadir <=0.5 ng/mL, 91% vs. 59%, respectively). Conclusion: We have demonstrated excellent outcomes in low- to intermediate-risk patients treated with PPI, suggesting at least equivalent 5-year bNED rates and a greater proportion of men achieving lower PSA nadirs compared with 3D-CRT or

  1. A Monte Carlo investigation of lung brachytherapy treatment planning

    NASA Astrophysics Data System (ADS)

    Sutherland, J. G. H.; Furutani, K. M.; Thomson, R. M.

    2013-07-01

    Iodine-125 (125I) and Caesium-131 (131Cs) brachytherapy have been used in conjunction with sublobar resection to reduce the local recurrence of stage I non-small cell lung cancer compared with resection alone. Treatment planning for this procedure is typically performed using only a seed activity nomogram or look-up table to determine seed strand spacing for the implanted mesh. Since the post-implant seed geometry is difficult to predict, the nomogram is calculated using the TG-43 formalism for seeds in a planar geometry. In this work, the EGSnrc user-code BrachyDose is used to recalculate nomograms using a variety of tissue models for 125I and 131Cs seeds. Calculated prescription doses are compared to those calculated using TG-43. Additionally, patient CT and contour data are used to generate virtual implants to study the effects that post-implant deformation and patient-specific tissue heterogeneity have on perturbing nomogram-derived dose distributions. Differences of up to 25% in calculated prescription dose are found between TG-43 and Monte Carlo calculations with the TG-43 formalism underestimating prescription doses in general. Differences between the TG-43 formalism and Monte Carlo calculated prescription doses are greater for 125I than for 131Cs seeds. Dose distributions are found to change significantly based on implant deformation and tissues surrounding implants for patient-specific virtual implants. Results suggest that accounting for seed grid deformation and the effects of non-water media, at least approximately, are likely required to reliably predict dose distributions in lung brachytherapy patients.

  2. Stereotactic interstitial brachytherapy of malignant astrocytomas with remarks on postimplantation computed tomographic appearance

    SciTech Connect

    Willis, B.K.; Heilbrun, M.P.; Sapozink, M.D.; McDonald, P.R.

    1988-09-01

    Seventeen patients were treated with stereotactically implanted high activity iodine-125 seeds, 12 patients for recurrent malignant astrocytomas (Protocol I) and 5 patients for newly diagnosed glioblastomas (Protocol II). Total radiation dosage to the recurrent tumors in Protocol I, including prior external beam irradiation, averaged 13,500 cGy. In the follow-up period of 6 to 50 months, the survival rate was 93% at 6 months, 60% at 12 months, 50% at 18 months, and 38% at 24 months after implantation. In Protocol II, brachytherapy was used as an interstitial radiation boost to the conventional treatment of newly diagnosed glioblastomas. External beam therapy and interstitial brachytherapy provided 11,000 cGy to these tumors. In the follow-up period of 15 to 27 months, there was a 100% survival at 12 months, 75% at 18 months, and 25% at 24 months after implantation. Eight of our 17 patients required reoperation for persistent or recurrent mass lesions at 6 to 15 months postimplantation; 7 were found to harbor masses of radionecrosis containing nests of anaplastic astrocytes; 1 had frank tumor recurrence. Median survival in this group of patients requiring reoperation was 18.7 months postimplantation. In a review of postimplantation computed tomographic scans, significant mass effect and crossover of hypodensity or enhancement into the corpus callosum or opposite hemisphere were found to have prognostic significance; persistent areas of contrast enhancement and excessive peritumoral hypodensity did not.

  3. Brachytherapy Application With In Situ Dose Painting Administered by Gold Nanoparticle Eluters

    SciTech Connect

    Sinha, Neeharika; Cifter, Gizem; Sajo, Erno; Kumar, Rajiv; Sridhar, Srinivas; Nguyen, Paul L.; Cormack, Robert A.; Makrigiorgos, G. Mike; Ngwa, Wilfred

    2015-02-01

    Purpose: Recent studies show promise that administering gold nanoparticles (GNP) to tumor cells during brachytherapy could significantly enhance radiation damage to the tumor. A new strategy proposed for sustained administration of the GNP in prostate tumors is to load them into routinely used brachytherapy spacers for customizable in situ release after implantation. This in silico study investigated the intratumor biodistribution and corresponding dose enhancement over time due to GNP released from such GNP-loaded brachytherapy spacers (GBS). Method and Materials: An experimentally determined intratumoral diffusion coefficient (D) for 10-nm nanoparticles was used to estimate D for other sizes by using the Stokes-Einstein equation. GNP concentration profiles, obtained using D, were then used to calculate the corresponding dose enhancement factor (DEF) for each tumor voxel, using dose painting-by-numbers approach, for times relevant to the considered brachytherapy sources' lifetimes. The investigation was carried out as a function of GNP size for the clinically applicable low-dose-rate brachytherapy sources iodine-125 (I-125), palladium-103 (Pd-103), and cesium-131 (Cs-131). Results: Results showed that dose enhancement to tumor voxels and subvolumes during brachytherapy can be customized by varying the size of GNP released or eluted from the GBS. For example, using a concentration of 7 mg/g GNP, significant DEF (>20%) could be achieved 5 mm from a GBS after 5, 12, 25, 46, 72, 120, and 195 days, respectively, for GNP sizes of 2, 5, 10, 20, 30, and 50 nm and for 80 nm when treating with I-125. Conclusions: Analyses showed that using Cs-131 provides the highest dose enhancement to tumor voxels. However, given its relatively longer half-life, I-125 presents the most flexibility for customizing the dose enhancement as a function of GNP size. These findings provide a useful reference for further work toward development of potential new brachytherapy application with

  4. Comparison of methods for calculating glomerular filtration rate: Technetium-99m-DTPA scintigraphic analysis, protein-free and whole-plasma clearance of technetium-99m-DTPA and iodine-125-iothalamate clearance

    SciTech Connect

    Goates, J.J.; Morton, K.A.; Whooten, W.W.; Greenberg, H.E.; Datz, F.L.; Handy, J.E.; Scuderi, A.J.; Haakenstad, A.O.; Lynch, R.E. )

    1990-04-01

    True glomerular filtration rate (GFR) was measured in normal volunteers and in patients with normal and impaired renal function by the iothalamate clearance (IC) method of Sigman. Within 24 hr, GFR was also determined by two other methods: technetium-99m- ({sup 99m}Tc) DTPA scintigraphic analysis (SA) utilizing a modification of the Gates computer program, and by measuring disappearance of {sup 99m}Tc-DTPA from whole plasma (WPC) and from protein-free ultrafiltered plasma (PFPC). Determinations of GFR by IC and by PFPC methods were virtually identical (mean absolute error 5.36 ml/min, r = 0.99, p greater than 0.05). GFRs measured in protein-free, ultrafiltered plasma differed significantly from those obtained from whole plasma only in sicker patients and in those taking multiple medications (in whom alterations in protein-binding of DTPA may be seen). The SA method correlated less well with the iodine-125-({sup 125}I) IC method than did either the protein-free or whole-plasma clearance methods (mean absolute error 32.36 ml/min, r = 0.74, p less than 0.05). However, the SA method provided useful information with respect to differential (split) renal function.

  5. Prostate brachytherapy - discharge

    MedlinePlus

    Implant therapy - prostate cancer - discharge; Radioactive seed placement - discharge ... You had a procedure called brachytherapy to treat prostate cancer. Your treatment lasted 30 minutes or more, depending ...

  6. [Valorisation of brachytherapy and medico-economic considerations].

    PubMed

    Pommier, P; Morelle, M; Millet-Lagarde, F; Peiffert, D; Gomez, F; Perrier, L

    2013-04-01

    Economic data in the literature for brachytherapy are still sparse and heterogeneous, with few controlled prospective studies and a perspective most often limited to those of the provider (health insurances). Moreover, these observation and conclusions are difficult to generalize in France. The prospective health economic studies performed in France in the framework of a national program to sustain innovative and costly therapies (STIC program) launched by the French cancer national institute are therefore of most importance. With the exception of prostate brachytherapy with permanent seeds, the valorisation of the brachytherapy activity by the French national health insurance does not take into account the degree of complexity and the real costs supported by health institutions (i.e. no specific valorisation for 3D image-based treatment planning and dose optimization and for the use of pulsed dose rate brachytherapy).

  7. Acute urinary morbidity after a permanent 125I implantation for localized prostate cancer.

    PubMed

    Ohga, Saiji; Nakamura, Katsumasa; Shioyama, Yoshiyuki; Tatsugami, Katsunori; Sasaki, Tomonari; Nonoshita, Takeshi; Yoshitake, Tadamasa; Asai, Kaori; Hirata, Hideki; Naito, Seiji; Honda, Hiroshi

    2014-11-01

    We evaluated the predictive factors of acute urinary morbidity (AUM) after prostate brachytherapy. From November 2005 to January 2007, 62 patients with localized prostate cancer were treated using brachytherapy. The (125)Iodine ((125)I) seed-delivering method was a modified peripheral pattern. The prescribed dose was 144 Gy. Urinary morbidity was scored at 3 months after implantation. The clinical and treatment parameters were analysed for correlation with AUM. In particular, in this study, Du90 (the minimal dose received by 90% of the urethra), Dup90 (the minimal dose received by 90% of the proximal half of the urethra on the bladder side) and Dud90 (the minimal dose received by 90% of the distal half of the urethra on the penile side) were analysed. We found that 43 patients (69.4%) experienced acute urinary symptoms at 3 months after implantation. Of them, 40 patients had Grade 1 AUM, one patient had Grade 2 pain, and two patients had Grade 2 urinary frequency. None of the patients had ≥Grade 3. Univariate and multivariate analysis revealed that Du90 and Dup90 were significantly correlated with AUM. In this study, Du90 and Dup90 were the most significant predictors of AUM after prostate brachytherapy.

  8. Advancements in brachytherapy.

    PubMed

    Tanderup, Kari; Ménard, Cynthia; Polgar, Csaba; Lindegaard, Jacob Christian; Kirisits, Christian; Pötter, Richard

    2017-01-15

    Brachytherapy is a radiotherapy modality associated with a highly focal dose distribution. Brachytherapy treats the cancer tissue from the inside, and the radiation does not travel through healthy tissue to reach the target as with external beam radiotherapy techniques. The nature of brachytherapy makes it attractive for boosting limited size target volumes to very high doses while sparing normal tissues. Significant developments over the last decades have increased the use of 3D image guided procedures with the utilization of CT, MRI, US and PET. This has taken brachytherapy to a new level in terms of controlling dose and demonstrating excellent clinical outcome. Interests in focal, hypofractionated and adaptive treatments are increasing, and brachytherapy has significant potential to develop further in these directions with current and new treatment indications.

  9. Prostate brachytherapy in Ghana: our initial experience

    PubMed Central

    Yarney, Joel; Vanderpuye, Verna; Akpakli, Evans; Tagoe, Samuel; Sasu, Evans

    2016-01-01

    Purpose This study presents the experience of a brachytherapy team in Ghana with a focus on technology transfer and outcome. The team was initially proctored by experienced physicians from Europe and South Africa. Material and methods A total of 90 consecutive patients underwent either brachytherapy alone or brachytherapy in combination with external beam radiotherapy for prostate carcinoma between July 2008 and February 2014 at Korle Bu Teaching Hospital, Accra, Ghana. Patients were classified as low-risk, intermediate, and high-risk according to the National Comprehensive Cancer Network (NCCN) criteria. All low-risk and some intermediate risk group patients were treated with seed implantation alone. Some intermediate and all high-risk group patients received brachytherapy combined with external beam radiotherapy. Results The median patient age was 64.0 years (range 46-78 years). The median follow-up was 58 months (range 18-74 months). Twelve patients experienced biochemical failure including one patient who had evidence of metastatic disease and died of prostate cancer. Freedom from biochemical failure rates for low, intermediate, and high-risk cases were 95.4%, 90.9%, and 70.8%, respectively. Clinical parameters predictive of biochemical outcome included: clinical stage, Gleason score, and risk group. Pre-treatment prostate specific antigen (PSA) was not a statistically significant predictor of biochemical failure. Sixty-nine patients (76.6%) experienced grade 1 urinary symptoms in the form of frequency, urgency, and poor stream. These symptoms were mostly self-limiting. Four patients needed catheterization for urinary retention (grade 2). One patient developed a recto urethral fistula (grade 3) following banding for hemorrhoids. Conclusions Our results compare favorably with those reported by other institutions with more extensive experience. We believe therefore that, interstitial permanent brachytherapy can be safely and effectively performed in a

  10. [Brachytherapy for sarcomas].

    PubMed

    Ducassou, A; Haie-Méder, C; Delannes, M

    2016-10-01

    The standard of care for local treatment for extremities soft tissue sarcomas relies on conservative surgery combined with external beam radiotherapy. Brachytherapy can be realized instead of external beam radiotherapy in selected cases, or more often used as a boost dose on a limited volume on the area at major risk of relapse, especially if a microscopic positive resection is expected. Close interaction and communication between radiation oncologists and surgeons are mandatory at the time of implantation to limit the risk of side effects. Long-term results are available for low-dose rate brachytherapy. Nowadays, pulsed dose rate or high-dose-rate brachytherapy are more often used. Brachytherapy for paediatric sarcomas is rare, and has to be managed in reference centres.

  11. Delivery systems for brachytherapy.

    PubMed

    de la Puente, Pilar; Azab, Abdel Kareem

    2014-10-28

    Brachytherapy is described as the short distance treatment of cancer with a radioactive isotope placed on, in, or near the lesions or tumor to be treated. The main advantage of brachytherapy compared with external beam radiation (EBR) is the improved localized delivery of dose to the target volume of interest, thus normal tissue irradiation is reduced. The precise and targeted nature of brachytherapy provides a number of key benefits for the effective treatment of cancer such as efficacy, minimized risk of side effects, short treatment times, and cost-effectiveness. Brachytherapy devices have yielded promising results in preclinical and clinical studies. However, brachytherapy can only be used in localized and relatively small tumors. Although the introduction of new delivery devices allows the treatment of more complex tumor sites, with wider range of dose rate for improving treatment efficacy and reduction of side effects, a better understanding about the safety, efficacy, and accuracy of these systems is required, and further development of new techniques is warranted. Therefore, this review focuses on the delivery devices for brachytherapy and their application in prostate, breast, brain, and other tumor sites.

  12. ALGEBRA: ALgorithm for the heterogeneous dosimetry based on GEANT4 for BRAchytherapy.

    PubMed

    Afsharpour, H; Landry, G; D'Amours, M; Enger, S; Reniers, B; Poon, E; Carrier, J-F; Verhaegen, F; Beaulieu, L

    2012-06-07

    Task group 43 (TG43)-based dosimetry algorithms are efficient for brachytherapy dose calculation in water. However, human tissues have chemical compositions and densities different than water. Moreover, the mutual shielding effect of seeds on each other (interseed attenuation) is neglected in the TG43-based dosimetry platforms. The scientific community has expressed the need for an accurate dosimetry platform in brachytherapy. The purpose of this paper is to present ALGEBRA, a Monte Carlo platform for dosimetry in brachytherapy which is sufficiently fast and accurate for clinical and research purposes. ALGEBRA is based on the GEANT4 Monte Carlo code and is capable of handling the DICOM RT standard to recreate a virtual model of the treated site. Here, the performance of ALGEBRA is presented for the special case of LDR brachytherapy in permanent prostate and breast seed implants. However, the algorithm is also capable of handling other treatments such as HDR brachytherapy.

  13. ALGEBRA: ALgorithm for the heterogeneous dosimetry based on GEANT4 for BRAchytherapy

    NASA Astrophysics Data System (ADS)

    Afsharpour, H.; Landry, G.; D'Amours, M.; Enger, S.; Reniers, B.; Poon, E.; Carrier, J.-F.; Verhaegen, F.; Beaulieu, L.

    2012-06-01

    Task group 43 (TG43)-based dosimetry algorithms are efficient for brachytherapy dose calculation in water. However, human tissues have chemical compositions and densities different than water. Moreover, the mutual shielding effect of seeds on each other (interseed attenuation) is neglected in the TG43-based dosimetry platforms. The scientific community has expressed the need for an accurate dosimetry platform in brachytherapy. The purpose of this paper is to present ALGEBRA, a Monte Carlo platform for dosimetry in brachytherapy which is sufficiently fast and accurate for clinical and research purposes. ALGEBRA is based on the GEANT4 Monte Carlo code and is capable of handling the DICOM RT standard to recreate a virtual model of the treated site. Here, the performance of ALGEBRA is presented for the special case of LDR brachytherapy in permanent prostate and breast seed implants. However, the algorithm is also capable of handling other treatments such as HDR brachytherapy.

  14. Plaque Brachytherapy for Uveal Melanoma: A Vision Prognostication Model

    SciTech Connect

    Khan, Niloufer; Khan, Mohammad K.; Bena, James; Macklis, Roger; Singh, Arun D.

    2012-11-01

    Purpose: To generate a vision prognostication model after plaque brachytherapy for uveal melanoma. Methods and Materials: All patients with primary single ciliary body or choroidal melanoma treated with iodine-125 or ruthenium-106 plaque brachytherapy between January 1, 2005, and June 30, 2010, were included. The primary endpoint was loss of visual acuity. Only patients with initial visual acuity better than or equal to 20/50 were used to evaluate visual acuity worse than 20/50 at the end of the study, and only patients with initial visual acuity better than or equal to 20/200 were used to evaluate visual acuity worse than 20/200 at the end of the study. Factors analyzed were sex, age, cataracts, diabetes, tumor size (basal dimension and apical height), tumor location, and radiation dose to the tumor apex, fovea, and optic disc. Univariate and multivariable Cox proportional hazards were used to determine the influence of baseline patient factors on vision loss. Kaplan-Meier curves (log rank analysis) were used to estimate freedom from vision loss. Results: Of 189 patients, 92% (174) were alive as of February 1, 2011. At presentation, visual acuity was better than or equal to 20/50 and better than or equal to 20/200 in 108 and 173 patients, respectively. Of these patients, 44.4% (48) had post-treatment visual acuity of worse than 20/50 and 25.4% (44) had post-treatment visual acuity worse than 20/200. By multivariable analysis, increased age (hazard ratio [HR] of 1.01 [1.00-1.03], P=.05), increase in tumor height (HR of 1.35 [1.22-1.48], P<.001), and a greater total dose to the fovea (HR of 1.01 [1.00-1.01], P<.001) were predictive of vision loss. This information was used to develop a nomogram predictive of vision loss. Conclusions: By providing a means to predict vision loss at 3 years after treatment, our vision prognostication model can be an important tool for patient selection and treatment counseling.

  15. MRI-guided brachytherapy

    PubMed Central

    Tanderup, Kari; Viswanathan, Akila; Kirisits, Christian; Frank, Steven J.

    2014-01-01

    The application of MRI-guided brachytherapy has demonstrated significant growth during the last two decades. Clinical improvements in cervix cancer outcomes have been linked to the application of repeated MRI for identification of residual tumor volumes during radiotherapy. This has changed clinical practice in the direction of individualized dose administration, and mounting evidence of improved clinical outcome with regard to local control, overall survival as well as morbidity. MRI-guided prostate HDR and LDR brachytherapy has improved the accuracy of target and organs-at-risk (OAR) delineation, and the potential exists for improved dose prescription and reporting for the prostate gland and organs at risk. Furthermore, MRI-guided prostate brachytherapy has significant potential to identify prostate subvolumes and dominant lesions to allow for dose administration reflecting the differential risk of recurrence. MRI-guided brachytherapy involves advanced imaging, target concepts, and dose planning. The key issue for safe dissemination and implementation of high quality MRI-guided brachytherapy is establishment of qualified multidisciplinary teams and strategies for training and education. PMID:24931089

  16. Dosimetric audit in brachytherapy

    PubMed Central

    Bradley, D A; Nisbet, A

    2014-01-01

    Dosimetric audit is required for the improvement of patient safety in radiotherapy and to aid optimization of treatment. The reassurance that treatment is being delivered in line with accepted standards, that delivered doses are as prescribed and that quality improvement is enabled is as essential for brachytherapy as it is for the more commonly audited external beam radiotherapy. Dose measurement in brachytherapy is challenging owing to steep dose gradients and small scales, especially in the context of an audit. Several different approaches have been taken for audit measurement to date: thimble and well-type ionization chambers, thermoluminescent detectors, optically stimulated luminescence detectors, radiochromic film and alanine. In this work, we review all of the dosimetric brachytherapy audits that have been conducted in recent years, look at current audits in progress and propose required directions for brachytherapy dosimetric audit in the future. The concern over accurate source strength measurement may be essentially resolved with modern equipment and calibration methods, but brachytherapy is a rapidly developing field and dosimetric audit must keep pace. PMID:24807068

  17. ROPES eye plaque brachytherapy dosimetry for two models of (103)Pd seeds.

    PubMed

    Saidi, Pooneh; Sadeghi, Mahdi; Shirazi, Alireza; Tenreiro, Claudio

    2011-06-01

    Brachytherapy dose distributions are calculated for 15 mm ROPES eye plaque loaded with model Theragenics200 and IR06-(103)Pd seeds. The effects of stainless steel backing and Acrylic insert on dose distribution along the central axis of the eye plaque and at critical ocular structure are investigated. Monte Carlo simulation was carried out with the Version 5 of the MCNP. The dose at critical ocular structure by considering the eye composition was calculated. Results are compared with the calculated data for COMS eye plaque loaded with Theragenics200 palladium-103 seeds and model 6711 iodine-125 seed. The air kerma strength of the IR06-(103)Pd seed to deliver 85 Gy in apex of tumor in water medium was calculated to be 4.10 U/seed. Along the central axis of stainless steel plaque loaded with new (103)Pd seeds in Acrylic insert, the dose reduction relative to water is 6.9% at 5 mm (apex). Removal of the Acrylic insert from the plaque (replacing with water) did not make significantly difference in dose reduction results (~0.2%). The presence of the stainless steel backing results in dose enhancement near the plaque relative to water. Doses at points of interest are higher for ROPES eye plaque when compared to COMS eye plaque. The dosimetric parameters calculated in this work for the new palladium seed, showed that in dosimetry point of view, the IR06-(103)Pd seed is suitable for use in brachytherapy. The effect of Acrylic insert on dose distribution is negligible and the main effect on dose reduction is due to the presence of stainless steel plaque backing.

  18. Establishing High-Quality Prostate Brachytherapy Using a Phantom Simulator Training Program

    SciTech Connect

    Thaker, Nikhil G.; Kudchadker, Rajat J.; Swanson, David A.; Albert, Jeffrey M.; Bruno, Teresa L.; Prestidge, Bradley R.; Crook, Juanita M.; Cox, Brett W.; Potters, Louis; Moran, Brian J.; Keyes, Mira; Kuban, Deborah A.; Frank, Steven J.

    2014-11-01

    Purpose: To design and implement a unique training program that uses a phantom-based simulator to teach the process of prostate brachytherapy (PB) quality assurance and improve the quality of education. Methods and Materials: Trainees in our simulator program were practicing radiation oncologists, radiation oncology residents, and fellows of the American Brachytherapy Society. The program emphasized 6 core areas of quality assurance: patient selection, simulation, treatment planning, implant technique, treatment evaluation, and outcome assessment. Using the Iodine 125 ({sup 125}I) preoperative treatment planning technique, trainees implanted their ultrasound phantoms with dummy seeds (ie, seeds with no activity). Pre- and postimplant dosimetric parameters were compared and correlated using regression analysis. Results: Thirty-one trainees successfully completed the simulator program during the period under study. The mean phantom prostate size, number of seeds used, and total activity were generally consistent between trainees. All trainees met the V100 >95% objective both before and after implantation. Regardless of the initial volume of the prostate phantom, trainees' ability to cover the target volume with at least 100% of the dose (V100) was not compromised (R=0.99 pre- and postimplant). However, the V150 had lower concordance (R=0.37) and may better reflect heterogeneity control of the implant process. Conclusions: Analysis of implants from this phantom-based simulator shows a high degree of consistency between trainees and uniformly high-quality implants with respect to parameters used in clinical practice. This training program provides a valuable educational opportunity that improves the quality of PB training and likely accelerates the learning curve inherent in PB. Prostate phantom implantation can be a valuable first step in the acquisition of the required skills to safely perform PB.

  19. [Safety in brachytherapy].

    PubMed

    Marcié, S; Marinello, G; Peiffert, D; Lartigau, É

    2013-04-01

    No technique can now be used without previously considering the safety of patients, staff and public and risk management. This is the case for brachytherapy. The various aspects of brachytherapy are discussed for both the patient and the staff. For all, the risks must be minimized while achieving a treatment of quality. It is therefore necessary to establish a list as comprehensive as possible regardless of the type of brachytherapy (low, high, pulsed dose-rate). Then, their importance must be assessed with the help of their criticality. Radiation protection of personnel and public must take into account the many existing regulation texts. Four axes have been defined for the risk management for patients: organization, preparation, planning and implementation of treatment. For each axis, a review of risks is presented, as well as administrative, technical and medical dispositions for staff and the public.

  20. Longitudinal Magnetic Resonance Imaging Features of Glioblastoma Multiforme Treated With Radiotherapy With or Without Brachytherapy

    SciTech Connect

    Aiken, Ashley H. Chang, Susan M.; Larson, David; Butowski, Nicholas; Cha, Soonmee

    2008-12-01

    Purpose: To compare temporal patterns of recurrent contrast enhancement in patients with glioblastoma multiforme (GBM) treated with brachytherapy plus external beam radiotherapy (EBRT) vs. EBRT alone. Methods and Materials: We evaluated serial MRI scans for 15 patients who received brachytherapy followed by EBRT (6000 cGy) and 20 patients who received standard EBRT alone (5940-6000 cGy). Brachytherapy consisted of permanent, low-activity {sup 125}I seeds placed around the resection cavity at the time of initial gross total resection. Contrast enhancement (linear, nodular, feathery, or solid), serial progression, and location of contrast enhancement were described. Results: In the EBRT group, 14 patients demonstrated focal nodular contrast enhancement along the resection cavity within 4 months. The 6 remaining EBRT patients developed either transient linear enhancement or no abnormal enhancement. In the brachytherapy plus EBRT group, 7 patients initially developed linear rim enhancement within 4 months that progressed to feathery contrast enhancement over the course of 1 to 2 years. Histopathology confirmed radiation necrosis in all 7 patients. The remaining 8 brachytherapy patients eventually developed focal nodular contrast enhancement along the resection cavity and tumor recurrence. Conclusions: Our data suggest that longitudinal MRI features differ between GBM patients treated with EBRT vs. brachytherapy plus EBRT. In both groups, nodular enhancement adjacent to or remote from the resection cavity strongly suggested tumor recurrence. Feathery enhancement, which progressed from linear rim enhancement immediately adjacent to the cavity, seen only in brachytherapy patients, strongly indicated radiation necrosis.

  1. Brachytherapy for clinically localized prostate cancer: optimal patient selection.

    PubMed

    Kollmeier, Marisa A; Zelefsky, Michael J

    2011-10-01

    The objective of this review is to present an overview of each modality and delineate how to best select patients who are optimal candidates for these treatment approaches. Prostate brachytherapy as a curative modality for clinically localized prostate cancer has become increasingly utilized over the past decade; 25% of all early cancers are now treated this way in the United States (1). The popularity of this treatment strategy lies in the highly conformal nature of radiation dose, low morbidity, patient convenience, and high efficacy rates. Prostate brachytherapy can be delivered by either a permanent interstitial radioactive seed implantation (low dose rate [LDR]) or a temporary interstitial insertion of iridium-192 (Ir192) afterloading catheters. The objective of both of these techniques is to deliver a high dose of radiation to the prostate gland while exposing normal surrounding tissues to minimal radiation dose. Brachytherapy techniques are ideal to achieve this goal given the close proximity of the radiation source to tumor and sharp fall off of the radiation dose cloud proximate to the source. Brachytherapy provides a powerful means of delivering dose escalation above and beyond that achievable with intensity-modulated external beam radiotherapy alone. Careful selection of appropriate patients for these therapies, however, is critical for optimizing both disease-related outcomes and treatment-related toxicity.

  2. Dosimetric and technical aspects of intraoperative I-125 brachytherapy for stage I non-small cell lung cancer

    NASA Astrophysics Data System (ADS)

    Johnson, Mark; Colonias, Athanasios; Parda, David; Trombetta, Mark; Gayou, Olivier; Reitz, Bodo; Miften, Moyed

    2007-03-01

    Initial treatment outcome data from our institution for stage I non-small cell lung cancer (NSCLC) patients have shown that sublobar resection in combination with iodine-125 (I-125) brachytherapy is associated with recurrence rates of 2.0%, compared to 18.6% with sublobar resection alone. In this work, the technical and dosimetric aspects required to execute this procedure from the radiation oncology perspective as well as an analysis of the dose distributions of patients treated with this technique are presented. In this treatment technique, I-125 seeds in vicryl suture are embedded into vicryl mesh and surgically inserted providing a 2.0 cm margin on each side of the resection staple line. A nomogram is developed to determine the suture spacing in the vicryl mesh, as a function of seed activity in order to deliver 120 Gy at a distance of 0.5 cm above and below the seed array. Post-operative dosimetry consists of a CT-based planning and dose volume analysis. Dose distributions, dose volume histograms and mean dose data for lung are analysed in a group of patients. Dosimetric results show significant lung sparing with only a small volume of lung irradiated for all patients with mean lung dose values ranging from 1.5 Gy to 5.4 Gy. Lung brachytherapy with I-125 at the time of sublobar resection is a highly conformal option of dose delivery for stage I NSCLC patients with compromised physiologic reserve. Patient-related toxicity clinically measured by loss of pulmonary function and radiation-induced pneumonitis have not been linked to this procedure.

  3. Comparative cost-effectiveness of focal and total salvage 125I brachytherapy for recurrent prostate cancer after primary radiotherapy

    PubMed Central

    Piena, Marjanne A.; Steuten, Lotte M.G.; van der Voort van Zyp, Jochem R.N.; Moerland, Marinus A.; van Vulpen, Marco

    2016-01-01

    Purpose Focal salvage (FS) iodine 125 (125I) brachytherapy could be an effective treatment for locally radiorecurrent prostate cancer (PCa). Toxicity is often reduced compared to total salvage (TS) while cancer control can be maintained, which could increase cost-effectiveness. The current study estimates the incremental cost per quality-adjusted life year (QALY) of FS compared to TS. Material and methods A decision analytic Markov model was developed, which compares costs and QALYs associated with FS and TS. A 3-year time horizon was adopted with six month cycles, with a hospital perspective on costs. Probabilities for genitourinary (GU) and gastrointestinal (GI) toxicity and their impact on health-related quality of life (SF-36) were derived from clinical studies in the University Medical Center Utrecht (UMCU). Probabilistic sensitivity analysis, using 10,000 Monte Carlo simulations, was performed to quantify the joint decision uncertainty up to the recommended maximum willingness-to-pay threshold of €80,000/QALY. Results Focal salvage dominates TS as it results in less severe toxicity and lower treatment costs. Decision uncertainty is small, with a 97-100% probability for FS to be cost-effective compared to TS (€0-€80,000/QALY). Half of the difference in costs between FS and TS was explained by higher treatment costs of TS, the other half by higher incidence of severe toxicity. One-way sensitivity analyses show that model outcomes are most sensitive to utilities and probabilities for severe toxicity. Conclusions Focal salvage 125I brachytherapy dominates TS, as it has lower treatment costs and leads to less toxicity in our center. Larger comparative studies with longer follow-up are necessary to assess the exact influence on (biochemical disease free) survival and toxicity. PMID:28115953

  4. Sexual Function and the Use of Medical Devices or Drugs to Optimize Potency After Prostate Brachytherapy

    SciTech Connect

    Whaley, J. Taylor; Levy, Lawrence B.; Swanson, David A.; Pugh, Thomas J.; Kudchadker, Rajat J.; Bruno, Teresa L.; Frank, Steven J.

    2012-04-01

    Purpose: Prospective evaluation of sexual outcomes after prostate brachytherapy with iodine-125 seeds as monotherapy at a tertiary cancer care center. Methods and Materials: Subjects were 129 men with prostate cancer with I-125 seed implants (prescribed dose, 145 Gy) without supplemental hormonal or external beam radiation therapy. Sexual function, potency, and bother were prospectively assessed at baseline and at 1, 4, 8, and 12 months using validated quality-of-life self-assessment surveys. Postimplant dosimetry values, including dose to 10% of the penile bulb (D10), D20, D33, D50, D75, D90, and penile volume receiving 100% of the prescribed dose (V100) were calculated. Results: At baseline, 56% of patients recorded having optimal erections; at 1 year, 62% of patients with baseline erectile function maintained optimal potency, 58% of whom with medically prescribed sexual aids or drugs. Variables associated with pretreatment-to-posttreatment decline in potency were time after implant (p = 0.04) and age (p = 0.01). Decline in urinary function may have been related to decline in potency. At 1 year, 69% of potent patients younger than 70 years maintained optimal potency, whereas 31% of patients older than 70 maintained optimal potency (p = 0.02). Diabetes was related to a decline in potency (p = 0.05), but neither smoking nor hypertension were. For patients with optimal potency at baseline, mean sexual bother scores had declined significantly at 1 year (p < 0.01). Sexual potency, sexual function, and sexual bother scores failed to correlate with any dosimetric variable tested. Conclusions: Erections firm enough for intercourse can be achieved at 1 year after treatment, but most men will require medical aids to optimize potency. Although younger men were better able to maintain erections firm enough for intercourse than older men, there was no correlation between potency, sexual function, or sexual bother and penile bulb dosimetry.

  5. Low-dose-rate or high-dose-rate brachytherapy in treatment of prostate cancer – between options

    PubMed Central

    2013-01-01

    Purpose Permanent low-dose-rate (LDR-BT) and temporary high-dose-rate (HDR-BT) brachytherapy are competitive techniques for clinically localized prostate radiotherapy. Although a randomized trial will likely never to be conducted comparing these two forms of brachytherapy, a comparative analysis proves useful in understanding some of their intrinsic differences, several of which could be exploited to improve outcomes. The aim of this paper is to look for possible similarities and differences between both brachytherapy modalities. Indications and contraindications for monotherapy and for brachytherapy as a boost to external beam radiation therapy (EBRT) are presented. It is suggested that each of these techniques has attributes that advocates for one or the other. First, they represent the extreme ends of the spectrum with respect to dose rate and fractionation, and therefore have inherently different radiobiological properties. Low-dose-rate brachytherapy has the great advantage of being practically a one-time procedure, and enjoys a long-term follow-up database supporting its excellent outcomes and low morbidity. Low-dose-rate brachytherapy has been a gold standard for prostate brachytherapy in low risk patients since many years. On the other hand, HDR is a fairly invasive procedure requiring several sessions associated with a brief hospital stay. Although lacking in significant long-term data, it possesses the technical advantage of control over its postimplant dosimetry (by modulating the source dwell time and position), which is absent in LDR brachytherapy. This important difference in dosimetric control allows HDR doses to be escalated safely, a flexibility that does not exist for LDR brachytherapy. Conclusions Radiobiological models support the current clinical evidence for equivalent outcomes in localized prostate cancer with either LDR or HDR brachytherapy, using current dose regimens. At present, all available clinical data regarding these two techniques

  6. Effect of implanted brachytherapy seeds on optical fluence distribution: preliminary ex vivo study

    NASA Astrophysics Data System (ADS)

    Hetzel, Fred W.; Chen, Qun; Ding, Meisong; Newman, Francis; Dole, Kenneth C.; Huang, Zheng; Blanc, Dominique

    2007-02-01

    Photodynamic therapy (PDT) has gradually found its place in the treatment of malignant and non-malignant human diseases. Currently, interstitial PDT is being explored as an alternative modality for newly diagnosed and recurrent organ-confined prostate cancer. The interstitial PDT for the treatment of prostate cancer might be considered to treat prostates with permanent radioactive seeds implantation. However, the effect of implanted brachytherapy seeds on the optical fluence distribution of PDT light has not been studied before. This study investigated, for the first time, the effect of brachytherapy seed on the optical fluence distribution of 760 nm light in ex vivo models (meat and canine prostate).

  7. Intraoral angiosarcoma: treatment with a brachytherapy prosthesis.

    PubMed

    Rosen, Evan B; Ko, Eugene; Wolden, Suzanne; Huryn, Joseph M; Estilo, Cherry L

    2015-03-01

    Angiosarcomas are rare, malignant neoplasms of vascular origin that account for less than 1% of all soft tissue tumors. Angiosarcomas of the oral cavity are especially rare, and brachytherapy may be prescribed as a localized treatment to manage these malignancies. Intraoral brachytherapy requires collaboration between the radiation oncologist and a dental professional for the fabrication of the brachytherapy delivery prosthesis. This clinical report describes an intraoral angiosarcoma and the fabrication of an intraoral brachytherapy prosthesis to manage this malignancy.

  8. Magnetic resonance image guided brachytherapy.

    PubMed

    Tanderup, Kari; Viswanathan, Akila N; Kirisits, Christian; Frank, Steven J

    2014-07-01

    The application of magnetic resonance image (MRI)-guided brachytherapy has demonstrated significant growth during the past 2 decades. Clinical improvements in cervix cancer outcomes have been linked to the application of repeated MRI for identification of residual tumor volumes during radiotherapy. This has changed clinical practice in the direction of individualized dose administration, and resulted in mounting evidence of improved clinical outcome regarding local control, overall survival as well as morbidity. MRI-guided prostate high-dose-rate and low-dose-rate brachytherapies have improved the accuracy of target and organs-at-risk delineation, and the potential exists for improved dose prescription and reporting for the prostate gland and organs at risk. Furthermore, MRI-guided prostate brachytherapy has significant potential to identify prostate subvolumes and dominant lesions to allow for dose administration reflecting the differential risk of recurrence. MRI-guided brachytherapy involves advanced imaging, target concepts, and dose planning. The key issue for safe dissemination and implementation of high-quality MRI-guided brachytherapy is establishment of qualified multidisciplinary teams and strategies for training and education.

  9. Anisotropy characterization of I-125 seed with attached encapsulated cobalt chloride complex contrast agent markers for MRI-based prostate brachytherapy.

    PubMed

    Frank, Steven J; Tailor, Ramesh C; Kudchadker, Rajat J; Martirosyan, Karen S; Stafford, R Jason; Elliott, Andrew M; Swanson, David A; Sing, David; Choi, Jonathan; Mourtada, Firas; Ibbott, Geoffrey S

    2011-01-01

    We have developed a novel MRI marker for prostate brachytherapy. The purpose of this study was to evaluate the changes in anisotropy when cobalt chloride complex contrast agent encapsulated contrast agent markers (C4-ECAM) were placed adjacent to an iodine-125 (I-125) titanium seed, and to verify that the C4-ECAMs were visible on magnetic resonance imaging (MRI) after radiation exposure. Two C4-ECAMs were verified to be MRI visible in a phantom before radiation exposure. The C4-ECAMs were then attached to each end of a 12.7-U (10-mCi) I-125 titanium seed in a polymer tube. Anisotropy was measured and analyzed with the seed alone and with attached C4-ECAMs by suspending thermoluminescent dosimeters in a water phantom in 2 circles surrounding the radioactive source with radius of 1 or 2 cm. A T1-weighted MRI evaluation of C4-ECAMs was then performed after exposure to the amount of radiation typically delivered during 1 month of prostate brachytherapy. Measured values of the anisotropy function F(r, θ) for the I-125 seed with and without the C4-ECAMs were mutually statistically indistinguishable (standard error of the mean <4.2%) and agreed well with published TG-43 values for the bare seed. As expected, the anisotropy function ϕ(an)(r) for the 2 datasets (with and without C4-ECAMs) derived from the measured F(r, θ) did not exhibit statistically measurable difference. Both datasets showed agreement with the published TG-43 ϕ(an)(r) for the bare seed. The C4-ECAMs were well visualized by MRI after 1 month of radiation exposure. There were no changes in anisotropy when the C4-ECAMs were placed next to an I-125 radioactive seed, and the C4-ECAMs were visualized after radiation exposure.

  10. Anisotropy Characterization of I-125 Seed with Attached Encapsulated Cobalt Chloride Complex Contrast Agent Markers for MRI-Based Prostate Brachytherapy

    SciTech Connect

    Frank, Steven J.; Tailor, Ramesh C.; Kudchadker, Rajat J.; Martirosyan, Karen S.; Stafford, R. Jason; Elliott, Andrew M.; Swanson, David A.; Sing, David; Choi, Jonathan; Mourtada, Firas; Ibbott, Geoffrey S.

    2011-07-01

    We have developed a novel MRI marker for prostate brachytherapy. The purpose of this study was to evaluate the changes in anisotropy when cobalt chloride complex contrast agent encapsulated contrast agent markers (C4-ECAM) were placed adjacent to an iodine-125 (I-125) titanium seed, and to verify that the C4-ECAMs were visible on magnetic resonance imaging (MRI) after radiation exposure. Two C4-ECAMs were verified to be MRI visible in a phantom before radiation exposure. The C4-ECAMs were then attached to each end of a 12.7-U (10-mCi) I-125 titanium seed in a polymer tube. Anisotropy was measured and analyzed with the seed alone and with attached C4-ECAMs by suspending thermoluminescent dosimeters in a water phantom in 2 circles surrounding the radioactive source with radius of 1 or 2 cm. A T1-weighted MRI evaluation of C4-ECAMs was then performed after exposure to the amount of radiation typically delivered during 1 month of prostate brachytherapy. Measured values of the anisotropy function F(r, {theta}) for the I-125 seed with and without the C4-ECAMs were mutually statistically indistinguishable (standard error of the mean <4.2%) and agreed well with published TG-43 values for the bare seed. As expected, the anisotropy function {phi}{sub an}(r) for the 2 datasets (with and without C4-ECAMs) derived from the measured F(r, {theta}) did not exhibit statistically measurable difference. Both datasets showed agreement with the published TG-43 {phi}{sub an}(r) for the bare seed. The C4-ECAMs were well visualized by MRI after 1 month of radiation exposure. There were no changes in anisotropy when the C4-ECAMs were placed next to an I-125 radioactive seed, and the C4-ECAMs were visualized after radiation exposure.

  11. Prostate cancer brachytherapy: guidelines overview

    PubMed Central

    Białas, Brygida

    2012-01-01

    Prostate cancer, due to wide availability of PSA tests, is very often diagnosed in early stage, nowadays. This makes management of this disease even harder in every day oncology care. There is a wide range of treatment options including surgery, radiotherapy and active surveillance, but essential question is which treatment patient and oncologist should decide for. Due to recent publication of Prostate Cancer Results Study Group, in which brachytherapy is one of supreme curative options for prostate cancer, we decided to overview most present european and north american recommendations. National Comprehensive Cancer Network, American Society for Radiation Oncology, American Brachytherapy Society, European Association of Urology and Groupe Européen de Curiethérapie of European Society for Therapeutic Radiation Oncology guidelines are overviewed, particularly focusing on HDR and LDR brachytherapy. PMID:23349655

  12. Prostate cancer brachytherapy: guidelines overview.

    PubMed

    Wojcieszek, Piotr; Białas, Brygida

    2012-06-01

    Prostate cancer, due to wide availability of PSA tests, is very often diagnosed in early stage, nowadays. This makes management of this disease even harder in every day oncology care. There is a wide range of treatment options including surgery, radiotherapy and active surveillance, but essential question is which treatment patient and oncologist should decide for. Due to recent publication of Prostate Cancer Results Study Group, in which brachytherapy is one of supreme curative options for prostate cancer, we decided to overview most present european and north american recommendations. National Comprehensive Cancer Network, American Society for Radiation Oncology, American Brachytherapy Society, European Association of Urology and Groupe Européen de Curiethérapie of European Society for Therapeutic Radiation Oncology guidelines are overviewed, particularly focusing on HDR and LDR brachytherapy.

  13. Evaluation of the MIM Symphony treatment planning system for low-dose-rate- prostate brachytherapy.

    PubMed

    Dhanesar, Sandeep K; Lim, Tze Y; Du, Weiliang; Bruno, Teresa L; Frank, Steven J; Kudchadker, Rajat J

    2015-09-08

    MIM Symphony is a recently introduced low-dose-rate prostate brachytherapy treatment planning system (TPS). We evaluated the dosimetric and planning accuracy of this new TPS compared to the universally used VariSeed TPS. For dosimetric evaluation of the MIM Symphony version 5.4 TPS, we compared dose calculations from the MIM Symphony TPS with the formalism recommended by the American Association of Physicists in Medicine Task Group 43 report (TG-43) and those generated by the VariSeed version 8.0 TPS for iodine-125 (I-125; Models 6711 and IAI-125A), palladium-103 (Pd-103; Model 200), and cesium-131 (Cs-131; Model Cs-1). Validation was performed for both line source and point source approximations. As part of the treatment planning validation, first a QA phantom (CIRS Brachytherapy QA Phantom Model 045 SN#D7210-3) containing three ellipsoid objects with certified volumes was scanned in order to check the volume accuracy of the contoured structures in MIM Symphony. Then the DICOM data containing 100 patient plans from the VariSeed TPS were imported into the MIM Symphony TPS. The 100 plans included 25 each of I-125 pre-implant plans, Pd-103 pre-implant plans, I-125 Day 30 plans (i.e., from 1 month after implantation), and Pd-103 Day 30 plans. The dosimetric parameters (including prostate volume, prostate D90 values, and rectum V100 values) of the 100 plans were calculated independently on the two TPSs. Other TPS tests that were done included verification of source input and geometrical accuracy, data transfer between different planning systems, text printout, 2D dose plots, DVH printout, and template grid accuracy. According to the line source formalism, the dosimetric results between the MIM Symphony TPS and TG-43 were within 0.5% (0.02 Gy) for r > 1 cm. In the line source approximation validation, MIM Symphony TPS values agreed with VariSeed TPS values to within 0.5% (0.09 Gy) for r > 1 cm. Similarly, in point source approximation validation, the MIM Symphony values

  14. Brachytherapy dosimeter with silicon photomultipliers

    NASA Astrophysics Data System (ADS)

    Moutinho, L. M.; Castro, I. F. C.; Peralta, L.; Abreu, M. C.; Veloso, J. F. C. A.

    2015-07-01

    In-vivo and in-situ measurement of the radiation dose administered during brachytherapy faces several technical challenges, requiring a very compact, tissue-equivalent, linear and highly sensitive dosimeter, particularly in low-dose rate brachytherapy procedures, which use radioactive seeds with low energy and low dose deposition rate. In this work we present a scintillating optical fiber dosimeter composed of a flexible sensitive probe and a dedicated electronic readout system based on silicon photomultiplier photodetection, capable of operating both in pulse and current modes. The performance of the scintillating fiber optic dosimeter was evaluated in low energy regimes, using an X-ray tube operating at voltages of 40-50 kV and currents below 1 mA, to assess minimum dose response of the scintillating fiber. The dosimeter shows a linear response with dose and is capable of detecting mGy dose variations like an ionization chamber. Besides fulfilling all the requirements for a dosimeter in brachytherapy, the high sensitivity of this device makes it a suitable candidate for application in low-dose rate brachytherapy. According to Peralta and Rego [1], the BCF-10 and BCF-60 scintillating optical fibers used in dosimetry exhibit high variations in their sensitivity for photon beams in the 25-100 kVp energy range. Energy linearity for energies below 50 keV needs to be further investigated, using monochromatic X-ray photons.

  15. Intra-Operative Dosimetry in Prostate Brachytherapy

    DTIC Science & Technology

    2006-11-01

    phantoms and pre-recorded patient data. 15. SUBJECT TERMS Prostate Brachytherapy, X-ray reconstruction, C-arm, TRUS 16. SECURITY CLASSIFICATION...prostate brachytherapy system that provides dosimetry analysis (Aim-2), and evaluate the system experimentally on phantoms and pre-recorded patient data...prostate brachytherapy system to enable dosimetry calculation Aim-3: Experimental Validation: Evaluate the performance of the RUF system on phantoms and

  16. Image-based brachytherapy for cervical cancer

    PubMed Central

    Vargo, John A; Beriwal, Sushil

    2014-01-01

    Cervical cancer is the third most common cancer in women worldwide; definitive radiation therapy and concurrent chemotherapy is the accepted standard of care for patients with node positive or locally advanced tumors > 4 cm. Brachytherapy is an important part of definitive radiotherapy shown to improve overall survival. While results for two-dimensional X-ray based brachytherapy have been good in terms of local control especially for early stage disease, unexplained toxicities and treatment failures remain. Improvements in brachytherapy planning have more recently paved the way for three-dimensional image-based brachytherapy with volumetric optimization which increases tumor control, reduces toxicity, and helps predict outcomes. Advantages of image-based brachytherapy include: improved tumor coverage (especially for large volume disease), decreased dose to critical organs (especially for small cervix), confirmation of applicator placement, and accounting for sigmoid colon dose. A number of modalities for image-based brachytherapy have emerged including: magnetic resonance imaging (MRI), computed tomography (CT), CT-MRI hybrid, and ultrasound with respective benefits and outcomes data. For practical application of image-based brachytherapy the Groupe Europeen de Curietherapie-European Society for Therapeutic Radiology and Oncology Working Group and American Brachytherapy Society working group guideline serve as invaluable tools, additionally here-in we outline our institutional clinical integration of these guidelines. While the body of literature supporting image-based brachytherapy continues to evolve a number of uncertainties and challenges remain including: applicator reconstruction, increasing resource/cost demands, mobile four-dimensional targets and organs-at-risk, and accurate contouring of “grey zones” to avoid marginal miss. Ongoing studies, including the prospective EMBRACE (an international study of MRI-guided brachytherapy in locally advanced

  17. Image-based brachytherapy for cervical cancer.

    PubMed

    Vargo, John A; Beriwal, Sushil

    2014-12-10

    Cervical cancer is the third most common cancer in women worldwide; definitive radiation therapy and concurrent chemotherapy is the accepted standard of care for patients with node positive or locally advanced tumors > 4 cm. Brachytherapy is an important part of definitive radiotherapy shown to improve overall survival. While results for two-dimensional X-ray based brachytherapy have been good in terms of local control especially for early stage disease, unexplained toxicities and treatment failures remain. Improvements in brachytherapy planning have more recently paved the way for three-dimensional image-based brachytherapy with volumetric optimization which increases tumor control, reduces toxicity, and helps predict outcomes. Advantages of image-based brachytherapy include: improved tumor coverage (especially for large volume disease), decreased dose to critical organs (especially for small cervix), confirmation of applicator placement, and accounting for sigmoid colon dose. A number of modalities for image-based brachytherapy have emerged including: magnetic resonance imaging (MRI), computed tomography (CT), CT-MRI hybrid, and ultrasound with respective benefits and outcomes data. For practical application of image-based brachytherapy the Groupe Europeen de Curietherapie-European Society for Therapeutic Radiology and Oncology Working Group and American Brachytherapy Society working group guideline serve as invaluable tools, additionally here-in we outline our institutional clinical integration of these guidelines. While the body of literature supporting image-based brachytherapy continues to evolve a number of uncertainties and challenges remain including: applicator reconstruction, increasing resource/cost demands, mobile four-dimensional targets and organs-at-risk, and accurate contouring of "grey zones" to avoid marginal miss. Ongoing studies, including the prospective EMBRACE (an international study of MRI-guided brachytherapy in locally advanced cervical

  18. Iodine-125 metaraminol: A new platelet specific labeling agent

    SciTech Connect

    Ohmomo, Y.; Yokoyama, A.; Kawaii, K.; Horiuchi, K.; Saji, H.; Torizuka, K.

    1984-01-01

    In the search for a platelet specific labeling agent, Metaraminol (MA), which is a sympatomimetic amine used for the treatment of hypotension, cardiogenic shock and well recognized as a drug actively incorporated and accumulated in platelet, attracted the authors' attention. Using the classical chloramine-T iodination method, a high labeling efficiency near 98%, reaching a specific activity up to about 1000 Ci/mmole was obtained. Upon the harvest of platelet, only as platelet rich plasma (PRP), the labeling with this radiopharmaceutical was easily performed by incubation at 37/sup 0/C for 10 min. Labeling efficiency as high as 63.0 +- 3.1% at 24 x 10/sup 8/ cells/ml was obtained. In in-vitro studies, the unaltered state of I-125 MA labeled platelet, with their cellular functions fully retained was demonstrated. Pharmacological study indicated a specific incorporation of I-125 MA by active transport system similar to that of 5-HT, along with passive diffusion. Then the in-vivo study carried out in rabbits with induced thrombi on the femoral artery, showed rather rapid disappearance of the I-125 MA labeled autologous platelet radioactivity, from circulating blood reaching as high thrombus-to-blood activity ratio as 19.8+-4.3 within 30 min post-administration. This new platelet labeling agent, I-125 MA, has many advantages over the use of IN-111 oxine and holds considerable promise for thrombus imaging with single photon emission CT upon the availability of I-123 MA.

  19. Afterloading: The Technique That Rescued Brachytherapy

    SciTech Connect

    Aronowitz, Jesse N.

    2015-07-01

    Although brachytherapy had been established as a highly effective modality for the treatment of cancer, its application was threatened by mid-20th century due to appreciation of the radiation hazard to health care workers. This review examines how the introduction of afterloading eliminated exposure and ushered in a brachytherapy renaissance.

  20. TU-AB-201-10: Novel Conformal Skin Brachytherapy Device

    SciTech Connect

    Ferreira, C; Johnson, D; Ahmad, S; Rasmussen, K; Jung, J

    2015-06-15

    Purpose: A novel conformal skin brachytherapy (CSBT) device was developed to provide patient specific treatment for small inoperable lesions and irregular surfaces that are not good candidates for electron external beam, e.g. eyelids, nose, lips, ears, etc. Methods: A prototype was built and tested using radioactive seeds spaced by 1.5 mm attached to a 3D printed template. Seeds were allowed to move independently at treatment surface to conform to target geometry. Beta-emitter Praseodymium-142 (half-life: 19.12 h, average beta energy: 809 keV) and Iodine-125 Model 6711 (half-life: 59.4 days, average gamma energy: 28 keV) seeds were used to test the feasibility of the device in solid water phantom for different prescription depths and surface areas. Percent depth doses and dose profiles were analyzed. MCNPX2.6 Monte Carlo Simulation and Gafchromic EBT3 film measurements were performed for a single Pr-142 seed. Treatment with nineteen I-125 seeds was planned in BrachyVision and measured experimentally for a total dose of 500 cGy at 5.0 mm depth. Results: For a single Pr-142 seed, dose was 500.0 cGy at surface and 17.4 cGy at 5.00 mm. BrachyVision planned and film doses for I-125 seed matrix were 500 cGy and 473.5 cGy at 5 mm depth and 171.0 cGy and 201.0 cGy at 10 mm depth. Total covered surface area for Pr-142 and I-125 were 2.35 mm{sup 2} and 88.24 mm{sup 2} respectively. Profile dose fall-off showed to be very conformal to contact area with 50% of the total surface dose from a single Pr-142 and array of I-125 seeds being deposited at 0.72 mm and 0.65 mm respectively from the central axis. Conclusion: CSBT device provides a high conformal dose to small surfaces. BrachyVision can be used to predict clinical dose distributions for multiple seeds matrix. Different radioactive seeds can be used to suit prescription depth and treatment area.

  1. Prostate Brachytherapy in Men {>=}75 Years of Age

    SciTech Connect

    Merrick, Gregory S. Wallner, Kent E.; Galbreath, Robert W.; Butler, Wayne M.; Brammer, Sarah G.; Allen, Zachariah A.; Adamovich, Edward

    2008-10-01

    Purpose: To evaluate cause-specific survival (CSS), biochemical progression-free survival (bPFS), and overall survival (OS) in prostate cancer patients aged {>=}75 years undergoing brachytherapy with or without supplemental therapies. Methods and Materials: Between April 1995 and August 2004, 145 consecutive patients aged {>=}75 years underwent permanent prostate brachytherapy. Median follow-up was 5.8 years. Biochemical progression-free survival was defined by a prostate-specific antigen level {<=}0.40 ng/mL after nadir. Patients with metastatic prostate cancer or hormone-refractory disease without obvious metastases who died of any cause were classified as dead of prostate cancer. All other deaths were attributed to the immediate cause of death. Multiple clinical, treatment, and dosimetric parameters were evaluated for impact on survival. Results: Nine-year CSS, bPFS, and OS rates for the entire cohort were 99.3%, 97.1%, and 64.5%, respectively. None of the evaluated parameters predicted for CSS, whereas bPFS was most closely predicted by percentage positive biopsies. Overall survival and non-cancer deaths were best predicted by tobacco status. Thirty-seven patients have died, with 83.8% of the deaths due to cardiovascular disease (22 patients) or second malignancies (9 patients). To date, only 1 patient (0.7%) has died of metastatic prostate cancer. Conclusions: After brachytherapy, high rates of CSS and bPFS are noted in elderly prostate cancer patients. Overall, approximately 65% of patients are alive at 9 years, with survival most closely related to tobacco status. We believe our results support an aggressive locoregional approach in appropriately selected elderly patients.

  2. Real-time photoacoustic imaging of prostate brachytherapy seeds using a clinical ultrasound system

    NASA Astrophysics Data System (ADS)

    Kuo, Nathanael; Kang, Hyun Jae; Song, Danny Y.; Kang, Jin U.; Boctor, Emad M.

    2012-06-01

    Prostate brachytherapy is a popular prostate cancer treatment option that involves the permanent implantation of radioactive seeds into the prostate. However, contemporary brachytherapy procedure is limited by the lack of an imaging system that can provide real-time seed-position feedback. While many other imaging systems have been proposed, photoacoustic imaging has emerged as a potential ideal modality to address this need, since it could easily be incorporated into the current ultrasound system used in the operating room. We present such a photoacoustic imaging system built around a clinical ultrasound system to achieve the task of visualizing and localizing seeds. We performed several experiments to analyze the effects of various parameters on the appearance of brachytherapy seeds in photoacoustic images. We also imaged multiple seeds in an ex vivo dog prostate phantom to demonstrate the possibility of using this system in a clinical setting. Although still in its infancy, these initial results of a photoacoustic imaging system for the application of prostate brachytherapy seed localization are highly promising.

  3. Testicular shielding in penile brachytherapy

    PubMed Central

    Bindal, Arpita; Tambe, Chandrashekhar M.; Ghadi, Yogesh; Murthy, Vedang; Shrivastava, Shyam Kishore

    2015-01-01

    Purpose Penile cancer, although rare, is one of the common genitourinary cancers in India affecting mostly aged uncircumcised males. For patients presenting with small superficial lesions < 3 cm restricted to glans, surgery, radical external radiation or brachytherapy may be offered, the latter being preferred as it allows organ and function preservation. In patients receiving brachytherapy, testicular morbidity is not commonly addressed. With an aim to minimize and document the doses to testis after adequate shielding during radical interstitial brachytherapy for penile cancers, we undertook this study in 2 patients undergoing brachytherapy and forms the basis of this report. Material and methods Two patients with early stage penile cancer limited to the glans were treated with radical high-dose-rate (HDR) brachytherapy using interstitial implant. A total of 7-8 tubes were implanted in two planes, parallel to the penile shaft. A total dose of 44-48 Gy (55-60 Gy EQD2 doses with α/β = 10) was delivered in 11-12 fractions of 4 Gy each delivered twice daily. Lead sheets adding to 11 mm (4-5 half value layer) were interposed between the penile shaft and scrotum. The testicular dose was measured using thermoluminescent dosimeters. For each patient, dosimetry was done for 3 fractions and mean calculated. Results The cumulative testicular dose to left and right testis was 31.68 cGy and 42.79 cGy for patient A, and 21.96 cGy and 23.28 cGy for patient B. For the same patients, the mean cumulative dose measured at the posterior aspect of penile shaft was 722.15 cGy and 807.72 cGy, amounting to 16.4% and 16.8% of the prescribed dose. Hence, the application of lead shield 11 mm thick reduced testicular dose from 722-808 cGy to 21.96-42.57 cGy, an “absolute reduction” of 95.99 ± 1.5%. Conclusions With the use of a simple lead shield as described, we were able to effectively reduce testicular dose from “spermicidal” range to “oligospermic” range with possible

  4. Dynamic rotating-shield brachytherapy

    SciTech Connect

    Liu, Yunlong; Flynn, Ryan T.; Kim, Yusung; Yang, Wenjun; Wu, Xiaodong

    2013-12-15

    Purpose: To present dynamic rotating shield brachytherapy (D-RSBT), a novel form of high-dose-rate brachytherapy (HDR-BT) with electronic brachytherapy source, where the radiation shield is capable of changing emission angles during the radiation delivery process.Methods: A D-RSBT system uses two layers of independently rotating tungsten alloy shields, each with a 180° azimuthal emission angle. The D-RSBT planning is separated into two stages: anchor plan optimization and optimal sequencing. In the anchor plan optimization, anchor plans are generated by maximizing the D{sub 90} for the high-risk clinical-tumor-volume (HR-CTV) assuming a fixed azimuthal emission angle of 11.25°. In the optimal sequencing, treatment plans that most closely approximate the anchor plans under the delivery-time constraint will be efficiently computed. Treatment plans for five cervical cancer patients were generated for D-RSBT, single-shield RSBT (S-RSBT), and {sup 192}Ir-based intracavitary brachytherapy with supplementary interstitial brachytherapy (IS + ICBT) assuming five treatment fractions. External beam radiotherapy doses of 45 Gy in 25 fractions of 1.8 Gy each were accounted for. The high-risk clinical target volume (HR-CTV) doses were escalated such that the D{sub 2cc} of the rectum, sigmoid colon, or bladder reached its tolerance equivalent dose in 2 Gy fractions (EQD2 with α/β= 3 Gy) of 75 Gy, 75 Gy, or 90 Gy, respectively.Results: For the patients considered, IS + ICBT had an average total dwell time of 5.7 minutes/fraction (min/fx) assuming a 10 Ci{sup 192}Ir source, and the average HR-CTV D{sub 90} was 78.9 Gy. In order to match the HR-CTV D{sub 90} of IS + ICBT, D-RSBT required an average of 10.1 min/fx more delivery time, and S-RSBT required 6.7 min/fx more. If an additional 20 min/fx of delivery time is allowed beyond that of the IS + ICBT case, D-RSBT and S-RSBT increased the HR-CTV D{sub 90} above IS + ICBT by an average of 16.3 Gy and 9.1 Gy, respectively

  5. Dose to the Bladder Neck Is the Most Important Predictor for Acute and Late Toxicity After Low-Dose-Rate Prostate Brachytherapy: Implications for Establishing New Dose Constraints for Treatment Planning

    SciTech Connect

    Hathout, Lara; Folkert, Michael R.; Kollmeier, Marisa A.; Yamada, Yoshiya; Cohen, Gil'ad N.; Zelefsky, Michael J.

    2014-10-01

    Purpose: To identify an anatomic structure predictive for acute (AUT) and late (LUT) urinary toxicity in patients with prostate cancer treated with low-dose-rate brachytherapy (LDR) with or without external beam radiation therapy (EBRT). Methods and Materials: From July 2002 to January 2013, 927 patients with prostate cancer (median age, 66 years) underwent LDR brachytherapy with Iodine 125 (n=753) or Palladium 103 (n=174) as definitive treatment (n=478) and as a boost (n=449) followed by supplemental EBRT (median dose, 50.4 Gy). Structures contoured on the computed tomographic (CT) scan on day 0 after implantation included prostate, urethra, bladder, and the bladder neck, defined as 5 mm around the urethra between the catheter balloon and the prostatic urethra. AUT and LUT were assessed with the Common Terminology Criteria for Adverse Events, version4. Clinical and dosimetric factors associated with AUT and LUT were analyzed with Cox regression and receiver operating characteristic analysis to calculate area under the receiver operator curve (ROC) (AUC). Results: Grade ≥2 AUT and grade ≥2 LUT occurred in 520 patients (56%) and 154 patients (20%), respectively. No grade 4 toxicities were observed. Bladder neck D2cc retained a significant association with AUT (hazard ratio [HR], 1.03; 95% confidence interval [CI], 1.03-1.04; P<.0001) and LUT (HR, 1.01; 95% CI, 1.00-1.03; P=.014) on multivariable analysis. In a comparison of bladder neck with the standard dosimetric variables by use of ROC analysis (prostate V100 >90%, D90 >100%, V150 >60%, urethra D20 >130%), bladder neck D2cc >50% was shown to have the strongest prognostic power for AUT (AUC, 0.697; P<.0001) and LUT (AUC, 0.620; P<.001). Conclusions: Bladder neck D2cc >50% was the strongest predictor for grade ≥2 AUT and LUT in patients treated with LDR brachytherapy. These data support inclusion of bladder neck constraints into brachytherapy planning to decrease urinary toxicity.

  6. Tissue modeling schemes in low energy breast brachytherapy

    NASA Astrophysics Data System (ADS)

    Afsharpour, Hossein; Landry, Guillaume; Reniers, Brigitte; Pignol, Jean-Philippe; Beaulieu, Luc; Verhaegen, Frank

    2011-11-01

    Breast tissue is heterogeneous and is mainly composed of glandular (G) and adipose (A) tissues. The proportion of G versus A varies considerably among the population. The absorbed dose distributions in accelerated partial breast irradiation therapy with low energy photon brachytherapy sources are very sensitive to tissue heterogeneities. Current clinical algorithms use the recommendations of the AAPM TG43 report which approximates the human tissues by unit density water. The aim of this study is to investigate various breast tissue modeling schemes for low energy brachytherapy. A special case of breast permanent seed implant is considered here. Six modeling schemes are considered. Uniform and non-uniform water breast (UWB and NUWB) consider the density but neglect the effect of the composition of tissues. The uniform and the non-uniform G/A breast (UGAB and NUGAB) as well the age-dependent breast (ADB) models consider the effect of the composition. The segmented breast tissue (SBT) method uses a density threshold to distinguish between G and A tissues. The PTV D90 metric is used for the analysis and is based on the dose to water (D90(w,m)). D90(m,m) is also reported for comparison to D90(w,m). The two-month post-implant D90(w,m) averaged over 38 patients is smaller in NUWB than in UWB by about 4.6% on average (ranging from 5% to 13%). Large average differences of G/A breast models with TG43 (17% and 26% in UGAB and NUGAB, respectively) show that the effect of the chemical composition dominates the effect of the density on dose distributions. D90(w,m) is 12% larger in SBT than in TG43 when averaged. These differences can be as low as 4% or as high as 20% when the individual patients are considered. The high sensitivity of dosimetry on the modeling scheme argues in favor of an agreement on a standard tissue modeling approach to be used in low energy breast brachytherapy. SBT appears to generate the most geometrically reliable breast tissue models in this report. This

  7. Essure Permanent Birth Control

    MedlinePlus

    ... and Prosthetics Essure Permanent Birth Control Essure Permanent Birth Control Share Tweet Linkedin Pin it More sharing options ... Essure System Essure is a a permanently implanted birth control device for women (female sterilization). Implantation of Essure ...

  8. HDR brachytherapy for anal cancer

    PubMed Central

    Kovács, Gyoergy

    2014-01-01

    The challenge of treating anal cancer is to preserve the anal sphincter function while giving high doses to the tumor and sparing the organ at risk. For that reason there has been a shift from radical surgical treatment with colostomy to conservative treatment. Radiotherapy combined with chemotherapy has an important role in the treatment of anal cancer patients. New techniques as intensity modulated radiotherapy (IMRT) have shown reduced acute toxicity and high rates of local control in combination with chemotherapy compared to conventional 3-D radiotherapy. Not only external beam radio-chemotherapy treatment (EBRT) is an established method for primary treatment of anal cancer, brachytherapy (BT) is also an approved method. BT is well known for boost irradiation in combination with EBRT (+/– chemotherapy). Because of technical developments like modern image based 3D treatment planning and the possibility of intensity modulation in brachytherapy (IMBT), BT today has even more therapeutic potential than it had in the era of linear sources. The combination of external beam radiotherapy (EBRT) and BT allows the clinician to deliver higher doses to the tumor and to reduce dose to the normal issue. Improvements in local control and reductions in toxicity therefore become possible. Various BT techniques and their results are discussed in this work. PMID:24982770

  9. Characterization of Low-Energy Photon-Emitting Brachytherapy Sources with Modified Strengths for Applications in Focal Therapy

    NASA Astrophysics Data System (ADS)

    Reed, Joshua L.

    Permanent implants of low-energy photon-emitting brachytherapy sources are used to treat a variety of cancers. Individual source models must be separately characterized due to their unique geometry, materials, and radionuclides, which all influence their dose distributions. Thermoluminescent dosimeters (TLDs) are often used for dose measurements around low-energy photon-emitting brachytherapy sources. TLDs are typically calibrated with higher energy sources such as 60Co, which requires a correction for the change in the response of the TLDs as a function of photon energy. These corrections have historically been based on TLD response to x ray bremsstrahlung spectra instead of to brachytherapy sources themselves. This work determined the TLD intrinsic energy dependence for 125I and 103Pd sources relative to 60Co, which allows for correction of TLD measurements of brachytherapy sources with factors specific to their energy spectra. Traditional brachytherapy sources contain mobile internal components and large amounts of high-Z material such as radio-opaque markers and titanium encapsulations. These all contribute to perturbations and uncertainties in the dose distribution around the source. The CivaString is a new elongated 103Pd brachytherapy source with a fixed internal geometry, polymer encapsulation, and lengths ranging from 1 to 6 cm, which offers advantages over traditional source designs. This work characterized the CivaString source and the results facilitated the formal approval of this source for use in clinical treatments. Additionally, the accuracy of a superposition technique for dose calculation around the sources with lengths >1 cm was verified. Advances in diagnostic techniques are paving the way for focal brachytherapy in which the dose is intentionally modulated throughout the target volume to focus on subvolumes that contain cancer cells. Brachytherapy sources with variable longitudinal strength (VLS) are a promising candidate for use in focal

  10. LDR brachytherapy: can low dose rate hypersensitivity from the "inverse" dose rate effect cause excessive cell killing to peripherial connective tissues and organs?

    PubMed

    Leonard, B E; Lucas, A C

    2009-02-01

    Examined here are the possible effects of the "inverse" dose rate effect (IDRE) on low dose rate (LDR) brachytherapy. The hyper-radiosensitivity and induced radioresistance (HRS/IRR) effect benefits cell killing in radiotherapy, and IDRE and HRS/IRR seem to be generated from the same radioprotective mechanisms. We have computed the IDRE excess cell killing experienced in LDR brachytherapy using permanent seed implants. We conclude, firstly, that IDRE is a dose rate-dependent manifestation of HRS/IRR. Secondly, the presence of HRS/IRR or IDRE in a cell species or tissue must be determined by direct dose-response measurements. Thirdly, a reasonable estimate is that 50-80% of human adjoining connective and organ tissues experience IDRE from permanent implanted LDR brachytherapy. If IDRE occurs for tissues at point A for cervical cancer, the excess cell killing will be about a factor of 3.5-4.0 if the initial dose rate is 50-70 cGy h(-1). It is greater for adjacent tissues at lower dose rates and higher for lower initial dose rates at point A. Finally, higher post-treatment complications are observed in LDR brachytherapy, often for unknown reasons. Some of these are probably a result of IDRE excess cell killing. Measurements of IDRE need be performed for connective and adjacent organ tissues, i.e. bladder, rectum, urinary tract and small bowels. The measured dose rate-dependent dose responses should extended to <10 cGy h(-1) and involve multiple patients to detect patient variability. Results may suggest a preference for high dose rate brachytherapy or LDR brachytherapy without permanent retention of the implant seeds (hence the dose rates in peripheral tissues and organs remain above IDRE thresholds).

  11. 10 CFR 35.406 - Brachytherapy sources accountability.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 1 2011-01-01 2011-01-01 false Brachytherapy sources accountability. 35.406 Section 35.406 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy § 35... for all brachytherapy sources in storage or use. (b) As soon as possible after removing sources from...

  12. 10 CFR 35.406 - Brachytherapy sources accountability.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 1 2012-01-01 2012-01-01 false Brachytherapy sources accountability. 35.406 Section 35.406 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy § 35... for all brachytherapy sources in storage or use. (b) As soon as possible after removing sources from...

  13. 10 CFR 35.406 - Brachytherapy sources accountability.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 1 2014-01-01 2014-01-01 false Brachytherapy sources accountability. 35.406 Section 35.406 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy § 35... for all brachytherapy sources in storage or use. (b) As soon as possible after removing sources from...

  14. 10 CFR 35.406 - Brachytherapy sources accountability.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Brachytherapy sources accountability. 35.406 Section 35.406 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy § 35... for all brachytherapy sources in storage or use. (b) As soon as possible after removing sources from...

  15. 10 CFR 35.406 - Brachytherapy sources accountability.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 1 2013-01-01 2013-01-01 false Brachytherapy sources accountability. 35.406 Section 35.406 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy § 35... for all brachytherapy sources in storage or use. (b) As soon as possible after removing sources from...

  16. Brachytherapy next generation: robotic systems

    PubMed Central

    Popescu, Tiberiu; Kacsó, Alex Cristian; Pisla, Doina

    2015-01-01

    In a field dominated by external beam radiation therapy (EBRT), both the therapeutic and technical possibilities of brachytherapy (BT) are underrated, shadowed by protons and intensity modulated radiotherapy. Decreasing expertise and indications, as well as increasing lack of specific BT training for radiation therapy (RT) residents led to the real need of shortening its learning curve and making it more popular. Developing robotic BT devices can be a way to mitigate the above issues. There are many teams working at custom-made robotic BT platforms to perfect and overcome the limitations of the existing systems. This paper provides a picture of the current state-of-the-art in robotic assisted BT, as it also conveys the author's solution to the problem, a parallel robot that uses CT-guidance. PMID:26816510

  17. In vivo dosimetry in brachytherapy

    SciTech Connect

    Tanderup, Kari; Beddar, Sam; Andersen, Claus E.; Kertzscher, Gustavo; Cygler, Joanna E.

    2013-07-15

    In vivo dosimetry (IVD) has been used in brachytherapy (BT) for decades with a number of different detectors and measurement technologies. However, IVD in BT has been subject to certain difficulties and complexities, in particular due to challenges of the high-gradient BT dose distribution and the large range of dose and dose rate. Due to these challenges, the sensitivity and specificity toward error detection has been limited, and IVD has mainly been restricted to detection of gross errors. Given these factors, routine use of IVD is currently limited in many departments. Although the impact of potential errors may be detrimental since treatments are typically administered in large fractions and with high-gradient-dose-distributions, BT is usually delivered without independent verification of the treatment delivery. This Vision 20/20 paper encourages improvements within BT safety by developments of IVD into an effective method of independent treatment verification.

  18. {sup 106}Ruthenium Brachytherapy for Retinoblastoma

    SciTech Connect

    Abouzeid, Hana; Moeckli, Raphael; Gaillard, Marie-Claire; Beck-Popovic, Maja; Pica, Alessia; Zografos, Leonidas; Balmer, Aubin; Pampallona, Sandro; Munier, Francis L.

    2008-07-01

    Purpose: To evaluate the efficacy of {sup 106}Ru plaque brachytherapy for the treatment of retinoblastoma. Methods and Materials: We reviewed a retrospective, noncomparative case series of 39 children with retinoblastoma treated with {sup 106}Ru plaques at the Jules-Gonin Eye Hospital between October 1992 and July 2006, with 12 months of follow-up. Results: A total of 63 tumors were treated with {sup 106}Ru brachytherapy in 41 eyes. The median patient age was 27 months. {sup 106}Ru brachytherapy was the first-line treatment for 3 tumors (4.8%), second-line treatment for 13 (20.6%), and salvage treatment for 47 tumors (74.6%) resistant to other treatment modalities. Overall tumor control was achieved in 73% at 1 year. Tumor recurrence at 12 months was observed in 2 (12.5%) of 16 tumors for which {sup 106}Ru brachytherapy was used as the first- or second-line treatment and in 15 (31.9%) of 47 tumors for which {sup 106}Ru brachytherapy was used as salvage treatment. Eye retention was achieved in 76% of cases (31 of 41 eyes). Univariate and multivariate analyses revealed no statistically significant risk factors for tumor recurrence. Radiation complications included retinal detachment in 7 (17.1%), proliferative retinopathy in 1 (2.4%), and subcapsular cataract in 4 (9.7%) of 41 eyes. Conclusion: {sup 106}Ru brachytherapy is an effective treatment for retinoblastoma, with few secondary complications. Local vitreous seeding can be successfully treated with {sup 106}Ru brachytherapy.

  19. Brachytherapy in the Treatment of Cholangiocarcinoma

    SciTech Connect

    Shinohara, Eric T.; Guo Mengye; Mitra, Nandita; Metz, James M.

    2010-11-01

    Purpose: To examine the role of brachytherapy in the treatment of cholangiocarcinomas in a relatively large group of patients. Methods and Materials: Using the Surveillance, Epidemiology and End Results database, a total of 193 patients with cholangiocarcinoma treated with brachytherapy were identified for the period 1988-2003. The primary analysis compared patients treated with brachytherapy (with or without external-beam radiation) with those who did not receive radiation. To try to account for confounding variables, propensity score and sensitivity analyses were used. Results: There was a significant difference between patients who received radiation (n = 193) and those who did not (n = 6859) with regard to surgery (p < 0.0001), race (p < 0.0001), stage (p < 0.0001), and year of diagnosis (p <0.0001). Median survival for patients treated with brachytherapy was 11 months (95% confidence interval [CI] 9-13 months), compared with 4 months for patients who received no radiation (p < 0.0001). On multivariable analysis (hazard ratio [95% CI]) brachytherapy (0.79 [0.66-0.95]), surgery (0.50 [0.46-0.53]), year of diagnosis (1998-2003: 0.66 [0.60-0.73]; 1993-1997: (0.96 [0.89-1.03; NS], baseline 1988-1992), and extrahepatic disease (0.84 [0.79-0.89]) were associated with better overall survival. Conclusions: To the authors' knowledge, this is the largest dataset reported for the treatment of cholangiocarcinomas with brachytherapy. The results of this retrospective analysis suggest that brachytherapy may improve overall survival. However, because of the limitations of the Surveillance, Epidemiology and End Results database, these results should be interpreted cautiously, and future prospective studies are needed.

  20. Incidence of Second Malignancies in Prostate Cancer Patients Treated With Low-Dose-Rate Brachytherapy and Radical Prostatectomy

    SciTech Connect

    Hamilton, Sarah Nicole; Tyldesley, Scott; Hamm, Jeremy; Jiang, Wei Ning; Keyes, Mira; Pickles, Tom; Lapointe, Vince; Kahnamelli, Adam; McKenzie, Michael; Miller, Stacy; Morris, W. James

    2014-11-15

    Purpose: To compare the second malignancy incidence in prostate cancer patients treated with brachytherapy (BT) relative to radical prostatectomy (RP) and to compare both groups with the cancer incidence in the general population. Methods and Materials: From 1998 to 2010, 2418 patients were treated with Iodine 125 prostate BT monotherapy at the British Columbia Cancer Agency, and 4015 referred patients were treated with RP. Cancer incidence was compared with the age-matched general population using standardized incidence ratios (SIRs). Pelvic malignancies included invasive and noninvasive bladder cancer and rectal cancer. Cox multivariable analysis was performed with adjustment for covariates to determine whether treatment (RP vs BT) was associated with second malignancy risk. Results: The median age at BT was 66 years and at RP 62 years. The SIR comparing BT patients with the general population was 1.06 (95% confidence interval [CI] 0.91-1.22) for second malignancy and was 1.53 (95% CI 1.12-2.04) for pelvic malignancy. The SIR comparing RP patients with the general population was 1.11 (95% CI 0.98-1.25) for second malignancy and was 1.11 (95% CI 0.82-1.48) for pelvic malignancy. On multivariable analysis, older age (hazard ratio [HR] 1.05) and smoking (HR 1.65) were associated with increased second malignancy risk (P<.0001). Radical prostatectomy was not associated with a decreased second malignancy risk relative to BT (HR 0.90, P=.43), even when excluding patients who received postprostatectomy external beam radiation therapy (HR 1.13, P=.25). Older age (HR 1.09, P<.0001) and smoking (HR 2.17, P=.0009) were associated with increased pelvic malignancy risk. Radical prostatectomy was not associated with a decreased pelvic malignancy risk compared with BT (HR 0.57, P=.082), even when excluding postprostatectomy external beam radiation therapy patients (HR 0.87, P=.56). Conclusions: After adjustment for covariates, BT patients did not have an increased second

  1. Late Urinary Side Effects 10 Years After Low-Dose-Rate Prostate Brachytherapy: Population-Based Results From a Multiphysician Practice Treating With a Standardized Protocol and Uniform Dosimetric Goals

    SciTech Connect

    Keyes, Mira Miller, Stacy; Pickles, Tom; Halperin, Ross; Kwan, Winkle; Lapointe, Vincent; McKenzie, Michael; Spadinger, Ingrid; Pai, Howard; Chan, Elisa K.; Morris, W. James

    2014-11-01

    Purpose: To determine late urinary toxicity (>12 months) in a large cohort of uniformly treated low-dose-rate prostate brachytherapy patients. Methods and Materials: From 1998 to 2009, 2709 patients with National Comprehensive Cancer Network–defined low-risk and low-tier intermediate-risk prostate cancer were treated with Iodine 125 ({sup 125}I) low-dose-rate prostate brachytherapy; 2011 patients with a minimum of 25 months of follow-up were included in the study. Baseline patients, treatment, implant factors, and late urinary toxicity (Radiation Therapy Oncology Group [RTOG] grading system and International Prostate Symptom Score [IPSS]) were recorded prospectively. Time to IPSS resolution, late RTOG genitourinary toxicity was examined with Kaplan-Meier and log-rank tests. Cox proportional hazards regression was done for individual covariates and multivariable models. Results: Median follow-up was 54.5 months (range, 2-13 years). Actuarial toxicity rates reached 27% and 10% (RTOG ≥2 and ≥3, respectively) at 9-13 years. Symptoms resolved quickly in the majority of patients (88% in 6-12 months). The prevalence of RTOG 0, 1, 2, 3, and 4 toxicity with a minimum of 7 years' follow-up was 70%, 21%, 6.4%, 2.3%, and 0.08%, respectively. Patients with a larger prostate volume, higher baseline IPSS, higher D90, acute toxicity, and age >70 years had more late RTOG ≥2 toxicity (all P≤.02). The IPSS resolved slower in patients with lower baseline IPSS and larger ultrasound prostate volume, those not receiving androgen deprivation therapy, and those with higher D90. The crude rate of RTOG 3 toxicity was 6%. Overall the rate of transurethral resection of the prostate was 1.9%; strictures, 2%; incontinence, 1.3%; severe symptoms, 1.8%; late catheterization, 1.3%; and hematuria, 0.8%. The majority (80%) resolved their symptoms in 6-12 months. Conclusion: Long-term urinary toxicity after brachytherapy is low. Although actuarial rates increase with longer follow

  2. Image guided Brachytherapy: The paradigm of Gynecologic and Partial Breast HDR Brachytherapy

    NASA Astrophysics Data System (ADS)

    Diamantopoulos, S.; Kantemiris, I.; Konidari, A.; Zaverdinos, P.

    2015-09-01

    High dose rate (HDR) brachytherapy uses high strength radioactive sources and temporary interstitial implants to conform the dose to target and minimize the treatment time. The advances of imaging technology enable accurate reconstruction of the implant and exact delineation of high-risk CTV and the surrounding critical structures. Furthermore, with sophisticated treatment planning systems, applicator devices and stepping source afterloaders, brachytherapy evolved to a more precise, safe and individualized treatment. At the Radiation Oncology Department of Metropolitan Hospital Athens, MRI guided HDR gynecologic (GYN) brachytherapy and accelerated partial breast irradiation (APBI) with brachytherapy are performed routinely. Contouring and treatment planning are based on the recommendations of the GEC - ESTRO Working group. The task of this presentation is to reveal the advantages of 3D image guided brachytherapy over 2D brachytherapy. Thus, two patients treated at our department (one GYN and one APBI) will be presented. The advantage of having adequate dose coverage of the high risk CTV and simultaneous low doses to the OARs when using 3D image- based brachytherapy will be presented. The treatment techniques, equipment issues, as well as implantation, imaging and treatment planning procedures will be described. Quality assurance checks will be treated separately.

  3. Adjuvant stereotactic permanent seed breast implant: A boost series in view of partial breast irradiation

    SciTech Connect

    Jansen, Nicolas . E-mail: nicolas.jansen@chu.ulg.ac.be; Deneufbourg, Jean-Marie; Nickers, Philippe

    2007-03-15

    Purpose: The aim of this study was to use permanent seed implants in the breast and describe our experience with 15 cases, using iodine seed implants as a tumor bed boost. Methods and Materials: Breasts were fixed with a thermoplastic sheet, a template bridge applied, the thorax scanned and the images rotated to be perpendicular to the implant axis. Skin, heart, and lung were delineated. A preplan was made, prescribing 50 Gy to the clinical target volume (CTV), consisting in this boost series of nearly a quadrant. Iodine (125) seeds were stereotactically implanted through the template, and results were checked with a postplan computed tomographic (CT) scan. Results: The breast was immobilized reproducibly. Simulation, scanning, and implant were performed without difficulties. Preplan CTV D90% (the dose delivered to 90% of the CTV) was 66 Gy, and postoperative fluoroscopic or CT scan checks were satisfactory. Pre- and postplan dose-volume histogram showed good organ sparing: mean postplan skin, heart, and lung V30 Gy (the organ volume receiving a dose of 30 Gy) of 2 {+-} 2.2 mL, 0.24 {+-} 0.34 mL, and 3.5 {+-} 5 mL, respectively. No short-term toxicity above Grade 1 was noted, except for transient Grade 3 neuropathy in 1 patient. Conclusions: Seeds remained in the right place, as assessed by fluoroscopy, absence of significant pre- to postplan dose-volume histogram change for critical organs, and total irradiated breast volume. The method could be proposed as a boost when high dosimetric selectivity is required (young patients after cardiotoxic chemotherapy for left-sided cancer). This boost series was a preliminary step before testing partial breast irradiation by permanent seed implant in a prospective trial.

  4. Brachytherapy and Local Excision for Sphincter Preservation in T1 and T2 Rectal Cancer

    SciTech Connect

    Grimard, Laval Stern, Hartley; Spaans, Johanna N. M.Sc.

    2009-07-01

    Purpose: To report long-term results of brachytherapy after local excision (LE) in the treatment of T1 and T2 rectal cancer at risk of recurrence due to residual subclinical disease. Methods and Materials: Between 1989 and 2007, 32 patients undergoing LE and brachytherapy were followed prospectively for a mean of 6.2 years. Estimates of local recurrence (LR), disease-specific survival (DSS), and overall survival (OS) were generated. Treatment-related toxicity and the effect of known prognostic factors were determined. Results: There were 8 LR (3 T1, 5 T2), of which 5 were salvaged surgically. Median time to the 8 LR was 14 months, and the 5-year rate of local control was 76%. Although there have been 9 deaths to date, only 5 were from disease. Five-year DSS and OS rates were 85% and 78%, respectively. There were 4 cases of Grade 2-3 radionecrosis and 1 case of mild stool incontinence. The sphincter was preserved in 27 of 32 patients. Conclusion: Local excision and adjuvant brachytherapy for T1 and T2 rectal cancer is an appealing treatment alternative to immediate radical resection, particularly in the frail and elderly who are unable to undergo major surgery, as well as for patients wanting to avoid a permanent colostomy.

  5. Cervix cancer brachytherapy: high dose rate.

    PubMed

    Miglierini, P; Malhaire, J-P; Goasduff, G; Miranda, O; Pradier, O

    2014-10-01

    Cervical cancer, although less common in industrialized countries, is the fourth most common cancer affecting women worldwide and the fourth leading cause of cancer death. In developing countries, these cancers are often discovered at a later stage in the form of locally advanced tumour with a poor prognosis. Depending on the stage of the disease, treatment is mainly based on a chemoradiotherapy followed by uterovaginal brachytherapy ending by a potential remaining tumour surgery or in principle for some teams. The role of irradiation is crucial to ensure a better local control. It has been shown that the more the delivered dose is important, the better the local results are. In order to preserve the maximum of organs at risk and to allow this dose escalation, brachytherapy (intracavitary and/or interstitial) has been progressively introduced. Its evolution and its progressive improvement have led to the development of high dose rate brachytherapy, the advantages of which are especially based on the possibility of outpatient treatment while maintaining the effectiveness of other brachytherapy forms (i.e., low dose rate or pulsed dose rate). Numerous innovations have also been completed in the field of imaging, leading to a progress in treatment planning systems by switching from two-dimensional form to a three-dimensional one. Image-guided brachytherapy allows more precise target volume delineation as well as an optimized dosimetry permitting a better coverage of target volumes.

  6. Interstitial hyperthermia in combination with brachytherapy.

    PubMed

    Coughlin, C T; Douple, E B; Strohbehn, J W; Eaton, W L; Trembly, B S; Wong, T Z

    1983-07-01

    Flexible coaxial cables were modified to serve as microwave antennas operating at a frequency of 915 MHz. These antennas were inserted into nylon afterloading tubes that had been implanted in tumors using conventional interstitial implantation techniques for iridium-192 seed brachytherapy. The tumor volume was heated to 42-45 degrees C within 15 minutes and heating was continued for a total of 1 hour per treatment. Immediately following a conventional brachytherapy dose and removal of the iridium seeds the tumors were heated again in a second treatment. This interstitial technique for delivering local hyperthermia should be compatible with most brachytherapy methods. The technique has proved so far to be practical and without complications. Temperature distributions obtained in tissue phantoms and a patient are described.

  7. Overview: Five decades of brachytherapy

    SciTech Connect

    Ellis, F.

    1986-01-01

    Brachytherapy started in 1930. Ra-226 was the radioisotope for cancer therapy at that time and much has been learned about its properties since then. One of the major findings at that time was output. When the author started, there was no T factor. People did not know how many R units were produced by 1.0 mg of radium filtered by 0.5 mm of platinum at 1.0 cm. So one was in a bit of chaos from that point of view. Eventually, that was settled in the 1930's. It was very exciting to find out that, although the national laboratories of the U.S., England, France and Germany had had values of this T factor varying from about five to seven (when they're only supposed to have less than 1% error); the value was really 8.3 and it was quite a landmark. This led to an improved knowledge of dose and effects. Developments over the next five decades are discussed in detail.

  8. Patterns of care study for brachytherapy: results of the questionnaire for the years 2002 and 2007 in The Netherlands

    PubMed Central

    Slotman, Ben J.; Guedea, Ferran; Ventura, Montse; Londres, Bradley; Francois, Guy

    2011-01-01

    Purpose The goal of the ESTRO Patterns of Care study for Brachytherapy in Europe (PCBE) 2002 was to develop an aid to analyse brachytherapy practices. A 2nd version of the PCB questionnaire was created for 2007. Data over 2007 were collected at the radiotherapy institutions in The Netherlands and compared with those from 2002. The aim of this study is to describe national brachytherapy practices, to demonstrate trends, and to provide data for rational health care planning. Material and methods Data were collected using a web-based questionnaire. For each centre, a local coordinator, responsible for coordinating the questionnaires and support of the further analysis was assigned. Data from the national cancer incidence registry was used for comparison with the data from the 21 Dutch departments. Results There was a decrease in low-dose rate equipment in parallel to an increase in both pulsed-dose rate and high-dose rate equipment. The use of 3D CT and MR based imaging techniques showed a slow rise. The most common clinical procedures were for prostate, gynaecological, and oesophageal tumours. A large increase (146%) in permanent implant prostate applications using 125I seeds was observed. The numbers of oesophageal and gynaecological treatments remained stable. There is concern on the low numbers of cases treated in some institutions for a few complex treatment sites. For head and neck, anal canal, paediatrics, bladder and eye interventions it ranged from 3-20 patients per year per institution. Conclusions The increase in number of patient treated with brachytherapy is in accordance with the increases in cancer incidence. The percentage of all radiotherapy patients treated with brachytherapy (approximately 5%) remained stable. The survey identified certain trends in resources and techniques, as well as areas of expected improvement and possible gain in clinical outcome. Data reported from this survey can be used for further planning of resources, facilities and

  9. Comparison of High-Dose Proton Radiotherapy and Brachytherapy in Localized Prostate Cancer: A Case-Matched Analysis

    SciTech Connect

    Coen, John J.; Zietman, Anthony L.; Rossi, Carl J.; Grocela, Joseph A.; Efstathiou, Jason A.; Yan, Yan; Shipley, William U.

    2012-01-01

    Purpose: To report a case-matched analysis comparing high-dose external-beam radiation (EBRT) for prostate cancer delivered on Proton Radiation Oncology Group (PROG) 95-09, a randomized trial, with permanent prostate brachytherapy over the same era. Methods: From 1996 to 1999, 196 patients were accrued to the high-dose arm (79.2 Gray equivalent (GyE) using photons and protons) of PROG 95-09 at the Massachusetts General Hospital and Loma Linda University Medical Center. Entry criteria specified T1-2 and prostate-specific antigen {<=}15 ng/mL. When Gleason score >7 was excluded, 177 men were left for case matching. At Massachusetts General Hospital, 203 similar patients were treated by a single brachytherapist from 1997 to 2002. Minimum follow-up was 3 years. Case matching, based on T stage, Gleason score, prostate-specific antigen, and age resulted in 141 matches (282 patients). Median follow-up was 8.6 and 7.4 years for EBRT and brachytherapy, respectively. The primary endpoint was biochemical failure (BF). Results: Using the Phoenix definition, the 8-year BF rates were 7.7% and 16.1% for EBRT and brachytherapy, respectively (p = 0.42). A stratified analysis was performed by risk group. In the EBRT group, 113 and 28 patients were low and intermediate risk, respectively. In the brachytherapy group, 118 and 23 were. When stratified by risk group, the BF rates were similar by either technique. Conclusions: High-dose EBRT and brachytherapy result in similar BF rates for men with localized prostate cancer. Comparative quality-of-life and cost-effectiveness studies are warranted.

  10. The American Brachytherapy Society Treatment Recommendations for Locally Advanced Carcinoma of the Cervix Part II: High Dose-Rate Brachytherapy

    PubMed Central

    Viswanathan, Akila N.; Beriwal, Sushil; De Los Santos, Jennifer; Demanes, D. Jeffrey; Gaffney, David; Hansen, Jorgen; Jones, Ellen; Kirisits, Christian; Thomadsen, Bruce; Erickson, Beth

    2012-01-01

    Purpose This report presents the 2011 update to the American Brachytherapy Society (ABS) high-dose-rate (HDR) brachytherapy guidelines for locally advanced cervical cancer. Methods Members of the American Brachytherapy Society (ABS) with expertise in cervical cancer brachytherapy formulated updated guidelines for HDR brachytherapy using tandem and ring, ovoids, cylinder or interstitial applicators for locally advanced cervical cancer were revised based on medical evidence in the literature and input of clinical experts in gynecologic brachytherapy. Results The Cervical Cancer Committee for Guideline Development affirms the essential curative role of tandem-based brachytherapy in the management of locally advanced cervical cancer. Proper applicator selection, insertion, and imaging are fundamental aspects of the procedure. Three-dimensional imaging with magnetic resonance or computed tomography or radiographic imaging may be used for treatment planning. Dosimetry must be performed after each insertion prior to treatment delivery. Applicator placement, dose specification and dose fractionation must be documented, quality assurance measures must be performed, and follow-up information must be obtained. A variety of dose/fractionation schedules and methods for integrating brachytherapy with external-beam radiation exist. The recommended tumor dose in 2 Gray (Gy) per fraction radiobiologic equivalence (EQD2) is 80–90 Gy, depending on tumor size at the time of brachytherapy. Dose limits for normal tissues are discussed. Conclusion These guidelines update those of 2000 and provide a comprehensive description of HDR cervical cancer brachytherapy in 2011. PMID:22265437

  11. MO-D-BRD-00: Electronic Brachytherapy

    SciTech Connect

    2015-06-15

    Electronic brachytherapy (eBT) has seen an insurgence of manufacturers entering the US market for use in radiation therapy. In addition to the established interstitial, intraluminary, and intracavitary applications of eBT, many centers are now using eBT to treat skin lesions. It is important for medical physicists working with electronic brachytherapy sources to understand the basic physics principles of the sources themselves as well as the variety of applications for which they are being used. The calibration of the sources is different from vendor to vendor and the traceability of calibrations has evolved as new sources came to market. In 2014, a new air-kerma based standard was introduced by the National Institute of Standards and Technology (NIST) to measure the output of an eBT source. Eventually commercial treatment planning systems should accommodate this new standard and provide NIST traceability to the end user. The calibration and commissioning of an eBT system is unique to its application and typically entails a list of procedural recommendations by the manufacturer. Commissioning measurements are performed using a variety of methods, some of which are modifications of existing AAPM Task Group protocols. A medical physicist should be familiar with the different AAPM Task Group recommendations for applicability to eBT and how to properly adapt them to their needs. In addition to the physical characteristics of an eBT source, the photon energy is substantially lower than from HDR Ir-192 sources. Consequently, tissue-specific dosimetry and radiobiological considerations are necessary when comparing these brachytherapy modalities and when making clinical decisions as a radiation therapy team. In this session, the physical characteristics and calibration methodologies of eBt sources will be presented as well as radiobiology considerations and other important clinical considerations. Learning Objectives: To understand the basic principles of electronic

  12. Evaluation of brachytherapy lung implant dose distributions from photon-emitting sources due to tissue heterogeneities

    SciTech Connect

    Yang Yun; Rivard, Mark J.

    2011-11-15

    Purpose: Photon-emitting brachytherapy sources are used for permanent implantation to treat lung cancer. However, the current brachytherapy dose calculation formalism assumes a homogeneous water medium without considering the influence of radiation scatter or tissue heterogeneities. The purpose of this study was to determine the dosimetric effects of tissue heterogeneities for permanent lung brachytherapy. Methods: The MCNP5 v1.40 radiation transport code was used for Monte Carlo (MC) simulations. Point sources with energies of 0.02, 0.03, 0.05, 0.1, 0.2, and 0.4 MeV were simulated to cover the range of pertinent brachytherapy energies and to glean dosimetric trends independent of specific radionuclide emissions. Source positions from postimplant CT scans of five patient implants were used for source coordinates, with dose normalized to 200 Gy at the center of each implant. With the presence of fibrosis (around the implant), cortical bone, lung, and healthy tissues, dose distributions and {sub PTV}DVH were calculated using the MCNP *FMESH4 tally and the NIST mass-energy absorption coefficients. This process was repeated upon replacing all tissues with water. For all photon energies, 10{sup 9} histories were simulated to achieve statistical errors (k = 1) typically of 1%. Results: The mean PTV doses calculated using tissue heterogeneities for all five patients changed (compared to dose to water) by only a few percent over the examined photon energy range, as did PTV dose at the implant center. The {sub PTV}V{sub 100} values were 81.2%, 90.0% (as normalized), 94.3%, 93.9%, 92.7%, and 92.2% for 0.02, 0.03, 0.05, 0.1, 0.2, and 0.4 MeV source photons, respectively. Relative to water, the maximum bone doses were higher by factors of 3.7, 5.1, 5.2, 2.4, 1.2, and 1.0 The maximum lung doses were about 0.98, 0.94, 0.91, 0.94, 0.97, and 0.99. Relative to water, the maximum healthy tissue doses at the mediastinal position were higher by factors of 9.8, 2.2, 1.3, 1.1, 1.1, and

  13. Automated intraoperative calibration for prostate cancer brachytherapy

    SciTech Connect

    Kuiran Chen, Thomas; Heffter, Tamas; Lasso, Andras; Pinter, Csaba; Abolmaesumi, Purang; Burdette, E. Clif; Fichtinger, Gabor

    2011-11-15

    Purpose: Prostate cancer brachytherapy relies on an accurate spatial registration between the implant needles and the TRUS image, called ''calibration''. The authors propose a new device and a fast, automatic method to calibrate the brachytherapy system in the operating room, with instant error feedback. Methods: A device was CAD-designed and precision-engineered, which mechanically couples a calibration phantom with an exact replica of the standard brachytherapy template. From real-time TRUS images acquired from the calibration device and processed by the calibration system, the coordinate transformation between the brachytherapy template and the TRUS images was computed automatically. The system instantly generated a report of the target reconstruction accuracy based on the current calibration outcome. Results: Four types of validation tests were conducted. First, 50 independent, real-time calibration trials yielded an average of 0.57 {+-} 0.13 mm line reconstruction error (LRE) relative to ground truth. Second, the averaged LRE was 0.37 {+-} 0.25 mm relative to ground truth in tests with six different commercial TRUS scanners operating at similar imaging settings. Furthermore, testing with five different commercial stepper systems yielded an average of 0.29 {+-} 0.16 mm LRE relative to ground truth. Finally, the system achieved an average of 0.56 {+-} 0.27 mm target registration error (TRE) relative to ground truth in needle insertion tests through the template in a water tank. Conclusions: The proposed automatic, intraoperative calibration system for prostate cancer brachytherapy has achieved high accuracy, precision, and robustness.

  14. Permanent Contraception for Women.

    PubMed

    Patil, Eva; Jensen, Jeffrey T

    2016-05-01

    Permanent contraception is a highly desired and commonly used contraceptive option for women around the world who desire never to become pregnant. Current methods of female permanent contraception require surgery. Postpartum tubal ligation and interval surgical tubal ligation are safe and effective, do not interfere with menstrual cycles, and require no ongoing cost or medical checkups. Hysteroscopic tubal occlusion offers a less invasive surgical approach, but requires an imaging study for verification of correct placement. However, not all women have access to a surgeon trained to provide permanent contraception, or they may face other prohibitive logistic or financial burdens. The development of novel permanent contraception methods that are immediately effective and/or nonsurgical could help improve access to and acceptability of permanent contraception. The expansion of permanent contraception options could help women achieve their family planning goals and reduce unintended pregnancies.

  15. Oscillating Permanent Magnets.

    ERIC Educational Resources Information Center

    Michaelis, M. M.; Haines, C. M.

    1989-01-01

    Describes several ways to partially levitate permanent magnets. Computes field line geometries and oscillation frequencies. Provides several diagrams illustrating the mechanism of the oscillation. (YP)

  16. State-of-the-art: prostate LDR brachytherapy.

    PubMed

    Voulgaris, S; Nobes, J P; Laing, R W; Langley, S E M

    2008-01-01

    This article on low dose rate (LDR) prostate brachytherapy reviews long-term results, patient selection and quality of life issues. Mature results from the United States and United Kingdom are reported and issues regarding definitions of biochemical failure are discussed. Latest data comparing brachytherapy with radical prostatectomy or no definitive treatment and also the risk of secondary malignancies after prostate brachytherapy are presented. Urological parameters of patient selection and quality of life issues concerning urinary, sexual and bowel function are reviewed. The position of prostate brachytherapy next to surgery as a first-line treatment modality is demonstrated.

  17. Study of Dosimetric and Thermal Properties of a Newly Developed Thermo-brachytherapy Seed for Treatment of Solid Tumors

    NASA Astrophysics Data System (ADS)

    Gautam, Bhoj R.

    Studies on the curative effects of hyperthermia and radiation therapy on treatment of cancer show strong evidence of synergistic enhancement when both radiation and hyperthermia treatment modalities are applied simultaneously. A variety of tissue heating approaches developed to date still fail to overcome essential limitations such as inadequate temperature control, temperature non-uniformity, and prolonged time delay between hyperthermia and radiation treatments. We propose a new self-regulating Thermo-brachytherapy (TB) seed, which serves as a source of both radiation and heat for concurrent administration of brachytherapy and hyperthermia. The proposed seed is based on the BestRTM Iodine-125 seed model 2301, where the tungsten marker core and the air gap are replaced with ferromagnetic material. The ferromagnetic core produces heat when subjected to an alternating electromagnetic (EM) field and effectively shuts off after reaching the Curie temperature (TC) of the ferromagnetic material, thus establishing temperature self-regulation. The seed has a ferromagnetic Ni-Cu alloy core having a Curie transition at a temperature of 52 °C. This study summarizes the design and development of the self regulating ferromagnetic core TB seed for the concurrent hyperthermia and brachytherapy treatments. An experimental study of the magnetic properties of the Ni1-xCu x (0.28≤ x ≤0.3) alloys, and the simulation studies of radiation and thermal distribution properties of the seed have been performed. A preliminary experiment for the ferromagnetic induction heating of Ni-Cu needles has been carried out to ensure the practical feasibility of the induction heating. Radiation dose characterizing parameters (dose rate constant and other TG-43 factors) were calculated using the Monte Carlo method. For the thermal characteristics, we studied a model consisting of single or multiple seeds placed in the central region of a cylindrical phantom using a finite-element analysis method

  18. Permanent magnet assembly

    DOEpatents

    Chell, Jeremy; Zimm, Carl B.

    2006-12-12

    A permanent magnet assembly is disclosed that is adapted to provide a magnetic field across an arc-shaped gap. Such a permanent magnet assembly can be used, for example, to provide a time-varying magnetic field to an annular region for use in a magnetic refrigerator.

  19. 10 CFR 35.400 - Use of sources for manual brachytherapy.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 1 2013-01-01 2013-01-01 false Use of sources for manual brachytherapy. 35.400 Section 35.400 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy § 35.400 Use of sources for manual brachytherapy. A licensee shall use only brachytherapy sources...

  20. 10 CFR 35.400 - Use of sources for manual brachytherapy.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 1 2011-01-01 2011-01-01 false Use of sources for manual brachytherapy. 35.400 Section 35.400 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy § 35.400 Use of sources for manual brachytherapy. A licensee shall use only brachytherapy sources...

  1. 10 CFR 35.400 - Use of sources for manual brachytherapy.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 1 2014-01-01 2014-01-01 false Use of sources for manual brachytherapy. 35.400 Section 35.400 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy § 35.400 Use of sources for manual brachytherapy. A licensee shall use only brachytherapy sources...

  2. 10 CFR 35.400 - Use of sources for manual brachytherapy.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Use of sources for manual brachytherapy. 35.400 Section 35.400 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy § 35.400 Use of sources for manual brachytherapy. A licensee shall use only brachytherapy sources...

  3. Modern head and neck brachytherapy: from radium towards intensity modulated interventional brachytherapy

    PubMed Central

    2014-01-01

    Intensity modulated brachytherapy (IMBT) is a modern development of classical interventional radiation therapy (brachytherapy), which allows the application of a high radiation dose sparing severe adverse events, thereby further improving the treatment outcome. Classical indications in head and neck (H&N) cancers are the face, the oral cavity, the naso- and oropharynx, the paranasal sinuses including base of skull, incomplete resections on important structures, and palliation. The application type can be curative, adjuvant or perioperative, as a boost to external beam radiation as well as without external beam radiation and with palliative intention. Due to the frequently used perioperative application method (intraoperative implantation of inactive applicators and postoperative performance of radiation), close interdisciplinary cooperation between surgical specialists (ENT-, dento-maxillary-facial-, neuro- and orbital surgeons), as well interventional radiotherapy (brachytherapy) experts are obligatory. Published results encourage the integration of IMBT into H&N therapy, thereby improving the prognosis and quality of life of patients. PMID:25834586

  4. Intra-Operative Dosimetry in Prostate Brachytherapy

    DTIC Science & Technology

    2007-11-01

    phantoms and pre-recorded patient data. 15. SUBJECT TERMS Prostate Brachytherapy, X-ray reconstruction, C-arm, TRUS 16. SECURITY CLASSIFICATION...system experimentally on phantoms and pre-recorded patient data (Aim-3). Algorithmic design (Aim-1) and experimental evaluation (Aim-3), will progress...Evaluate the performance of the RUF system on phantoms and pre- recorded patient data. (Neither of which require an IRB approval) B.3 Progress

  5. Rotating-shield brachytherapy for cervical cancer

    NASA Astrophysics Data System (ADS)

    Yang, Wenjun; Kim, Yusung; Wu, Xiaodong; Song, Qi; Liu, Yunlong; Bhatia, Sudershan K.; Sun, Wenqing; Flynn, Ryan T.

    2013-06-01

    In this treatment planning study, the potential benefits of a rotating shield brachytherapy (RSBT) technique based on a partially-shielded electronic brachytherapy source were assessed for treating cervical cancer. Conventional intracavitary brachytherapy (ICBT), intracavitary plus supplementary interstitial (IS+ICBT), and RSBT treatment plans for azimuthal emission angles of 180° (RSBT-180) and 45° (RSBT-45) were generated for five patients. For each patient, high-risk clinical target volume (HR-CTV) equivalent dose in 2 Gy fractions (EQD2) (α/β = 10 Gy) was escalated until bladder, rectum, or sigmoid colon tolerance EQD2 values were reached. External beam radiotherapy dose (1.8 Gy × 25) was accounted for, and brachytherapy was assumed to have been delivered in 5 fractions. IS+ICBT provided a greater HR-CTV D90 (minimum EQD2 to the hottest 90%) than ICBT. D90 was greater for RSBT-45 than IS+ICBT for all five patients, and greater for RSBT-180 than IS+ICBT for two patients. When the RSBT-45/180 plan with the lowest HR-CTV D90 that was greater than the D90 the ICBT or IS+ICBT plan was selected, the average (range) of D90 increases for RSBT over ICBT and IS+ICBT were 16.2 (6.3-27.2)and 8.5 (0.03-20.16) Gy, respectively. The average (range) treatment time increase per fraction of RSBT was 34.56 (3.68-70.41) min over ICBT and 34.59 (3.57-70.13) min over IS+ICBT. RSBT can increase D90 over ICBT and IS+ICBT without compromising organ-at-risk sparing. The D90 and treatment time improvements from RSBT depend on the patient and shield emission angle.

  6. Sensitivity of low energy brachytherapy Monte Carlo dose calculations to uncertainties in human tissue composition

    SciTech Connect

    Landry, Guillaume; Reniers, Brigitte; Murrer, Lars; Lutgens, Ludy; Bloemen-Van Gurp, Esther; Pignol, Jean-Philippe; Keller, Brian; Beaulieu, Luc; Verhaegen, Frank

    2010-10-15

    Purpose: The objective of this work is to assess the sensitivity of Monte Carlo (MC) dose calculations to uncertainties in human tissue composition for a range of low photon energy brachytherapy sources: {sup 125}I, {sup 103}Pd, {sup 131}Cs, and an electronic brachytherapy source (EBS). The low energy photons emitted by these sources make the dosimetry sensitive to variations in tissue atomic number due to the dominance of the photoelectric effect. This work reports dose to a small mass of water in medium D{sub w,m} as opposed to dose to a small mass of medium in medium D{sub m,m}. Methods: Mean adipose, mammary gland, and breast tissues (as uniform mixture of the aforementioned tissues) are investigated as well as compositions corresponding to one standard deviation from the mean. Prostate mean compositions from three different literature sources are also investigated. Three sets of MC simulations are performed with the GEANT4 code: (1) Dose calculations for idealized TG-43-like spherical geometries using point sources. Radial dose profiles obtained in different media are compared to assess the influence of compositional uncertainties. (2) Dose calculations for four clinical prostate LDR brachytherapy permanent seed implants using {sup 125}I seeds (Model 2301, Best Medical, Springfield, VA). The effect of varying the prostate composition in the planning target volume (PTV) is investigated by comparing PTV D{sub 90} values. (3) Dose calculations for four clinical breast LDR brachytherapy permanent seed implants using {sup 103}Pd seeds (Model 2335, Best Medical). The effects of varying the adipose/gland ratio in the PTV and of varying the elemental composition of adipose and gland within one standard deviation of the assumed mean composition are investigated by comparing PTV D{sub 90} values. For (2) and (3), the influence of using the mass density from CT scans instead of unit mass density is also assessed. Results: Results from simulation (1) show that variations

  7. Brachytherapy for the treatment of prostate cancer.

    PubMed

    Cesaretti, Jamie A; Stone, Nelson N; Skouteris, Vassilios M; Park, Janelle L; Stock, Richard G

    2007-01-01

    Low-dose rate brachytherapy has become a mainstream treatment option for men diagnosed with prostate cancer because of excellent long-term treatment outcomes in low-, intermediate-, and high-risk patients. Largely due to patient lead advocacy for minimally invasive treatment options, high-quality prostate implants have become widely available in the US, Europe, and Japan. The reason that brachytherapy results are reproducible in several different practice settings is because numerous implant quality factors have been defined over the last 20 years, which can be applied objectively to judge the success of the intervention both during and after the procedure. In addition, recent long-term follow-up studies have clarified that the secondary cancer incidence of brachytherapy is not clinically meaningful. In terms of future directions, the study of radiation repair genetics may allow for the counseling physician to better estimate any given patients risk for side effects, thereby substantially reducing the therapeutic uncertainties faced by patients choosing a prostate cancer intervention.

  8. 10 CFR 35.432 - Calibration measurements of brachytherapy sources.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 1 2013-01-01 2013-01-01 false Calibration measurements of brachytherapy sources. 35.432 Section 35.432 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy... Association of Physicists in Medicine that are made in accordance with paragraph (a) of this section. (c)...

  9. 10 CFR 35.432 - Calibration measurements of brachytherapy sources.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 1 2014-01-01 2014-01-01 false Calibration measurements of brachytherapy sources. 35.432 Section 35.432 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy... Association of Physicists in Medicine that are made in accordance with paragraph (a) of this section. (c)...

  10. 10 CFR 35.432 - Calibration measurements of brachytherapy sources.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 1 2012-01-01 2012-01-01 false Calibration measurements of brachytherapy sources. 35.432 Section 35.432 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy... Association of Physicists in Medicine that are made in accordance with paragraph (a) of this section. (c)...

  11. 10 CFR 35.432 - Calibration measurements of brachytherapy sources.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Calibration measurements of brachytherapy sources. 35.432 Section 35.432 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy... Association of Physicists in Medicine that are made in accordance with paragraph (a) of this section. (c)...

  12. 10 CFR 35.432 - Calibration measurements of brachytherapy sources.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 1 2011-01-01 2011-01-01 false Calibration measurements of brachytherapy sources. 35.432 Section 35.432 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy... Association of Physicists in Medicine that are made in accordance with paragraph (a) of this section. (c)...

  13. Improving the efficiency of image guided brachytherapy in cervical cancer

    PubMed Central

    Franklin, Adrian; Ajaz, Mazhar; Stewart, Alexandra

    2016-01-01

    Brachytherapy is an essential component of the treatment of locally advanced cervical cancers. It enables the dose to the tumor to be boosted whilst allowing relative sparing of the normal tissues. Traditionally, cervical brachytherapy was prescribed to point A but since the GEC-ESTRO guidelines were published in 2005, there has been a move towards prescribing the dose to a 3D volume. Image guided brachytherapy has been shown to reduce local recurrence, and improve survival and is optimally predicated on magnetic resonance imaging. Radiological studies, patient workflow, operative parameters, and intensive therapy planning can represent a challenge to clinical resources. This article explores the ways, in which 3D conformal brachytherapy can be implemented and draws findings from recent literature and a well-developed hospital practice in order to suggest ways to improve the efficiency and efficacy of a brachytherapy service. Finally, we discuss relatively underexploited translational research opportunities. PMID:28115963

  14. [How to prepare the brachytherapy of the future].

    PubMed

    Hannoun-Lévi, J-M; Peiffert, D

    2013-10-01

    For more than a century, brachytherapy has been a treatment of choice for delivering a high dose in a small volume. However, over the past 15 years, this irradiation technique has stalled. Even so, brachytherapy allows the delivery of the right dose at the right place by dispensing with target volume motion and repositioning. The evolution of brachytherapy can be based on a road-map including at least the following three points: the acquisition of clinical evidence, teaching and valuation of the procedures. The evolution of brachytherapy will be also impacted by technological considerations (end of the production of low dose rate 192 iridium wires). Regarding the evolution toward a personalized treatment, brachytherapy of the future should take its place as a partner of other modern external beam radiation techniques, be performed by experimented actors (physicians, physicists, technicians, etc.) who received adequate training, and be valued in proportion to the delivered medical service.

  15. Penile brachytherapy: Results for 49 patients

    SciTech Connect

    Crook, Juanita M. . E-mail: juanita.crook@rmp.uhn.on.ca; Jezioranski, John; Grimard, Laval; Esche, Bernd; Pond, G.

    2005-06-01

    Purpose: To report results for 49 men with squamous cell carcinoma (SCC) of the penis treated with primary penile interstitial brachytherapy at one of two institutions: the Ottawa Regional Cancer Center, Ottawa, and the Princess Margaret Hospital, Toronto, Ontario, Canada. Methods and Materials: From September 1989 to September 2003, 49 men (mean age, 58 years; range, 22-93 years) had brachytherapy for penile SCC. Fifty-one percent of tumors were T1, 33% T2, and 8% T3; 4% were in situ and 4% Tx. Grade was well differentiated in 31%, moderate in 45%, and poor in 2%; grade was unspecified for 20%. One tumor was verrucous. All tumors in Toronto had pulsed dose rate (PDR) brachytherapy (n = 23), whereas those in Ottawa had either Iridium wire (n 22) or seeds (n = 4). Four patients had a single plane implant with a plastic tube technique, and all others had a volume implant with predrilled acrylic templates and two or three parallel planes of needles (median, six needles). Mean needle spacing was 13.5 mm (range, 10-18 mm), mean dose rate was 65 cGy/h (range, 33-160 cGy/h), and mean duration was 98.8 h (range, 36-188 h). Dose rates for PDR brachytherapy were 50-61.2 cGy/h, with no correction in total dose, which was 60 Gy in all cases. Results: Median follow-up was 33.4 months (range, 4-140 months). At 5 years, actuarial overall survival was 78.3% and cause-specific survival 90.0%. Four men died of penile cancer, and 6 died of other causes with no evidence of recurrence. The cumulative incidence rate for never having experienced any type of failure at 5 years was 64.4% and for local failure was 85.3%. All 5 patients with local failure were successfully salvaged by surgery; 2 other men required penectomy for necrosis. The soft tissue necrosis rate was 16% and the urethral stenosis rate 12%. Of 8 men with regional failure, 5 were salvaged by lymph node dissection with or without external radiation. All 4 men with distant failure died of disease. Of 49 men, 42 had an intact

  16. Dose heterogeneity correction for low-energy brachytherapy sources using dual-energy CT images

    NASA Astrophysics Data System (ADS)

    Mashouf, S.; Lechtman, E.; Lai, P.; Keller, B. M.; Karotki, A.; Beachey, D. J.; Pignol, J. P.

    2014-09-01

    Permanent seed implant brachytherapy is currently used for adjuvant radiotherapy of early stage prostate and breast cancer patients. The current standard for calculation of dose around brachytherapy sources is based on the AAPM TG-43 formalism, which generates the dose in a homogeneous water medium. Recently, AAPM TG-186 emphasized the importance of accounting for tissue heterogeneities. We have previously reported on a methodology where the absorbed dose in tissue can be obtained by multiplying the dose, calculated by the TG-43 formalism, by an inhomogeneity correction factor (ICF). In this work we make use of dual energy CT (DECT) images to extract ICF parameters. The advantage of DECT over conventional CT is that it eliminates the need for tissue segmentation as well as assignment of population based atomic compositions. DECT images of a heterogeneous phantom were acquired and the dose was calculated using both TG-43 and TG-43 × \\text{ICF} formalisms. The results were compared to experimental measurements using Gafchromic films in the mid-plane of the phantom. For a seed implant configuration of 8 seeds spaced 1.5 cm apart in a cubic structure, the gamma passing score for 2%/2 mm criteria improved from 40.8% to 90.5% when ICF was applied to TG-43 dose distributions.

  17. Local tumor control after {sup 106}Ru brachytherapy of choroidal melanoma

    SciTech Connect

    Damato, Bertil . E-mail: Bertil@damato.co.uk; Patel, Imran; Campbell, Ian R.; Mayles, Helen M.; Errington, R. Douglas

    2005-10-01

    Purpose To report on local tumor control after {sup 106}Ru brachytherapy for choroidal melanoma. Methods and Materials A total of 458 patients with choroidal melanoma were treated at a single institution between January 1993 and December 2001. The tumors had a median longest basal dimension of 10.6 mm and a median height of 3.2 mm. The brachytherapy was administered using a 15- or 20-mm plaque. For posterior tumors, the plaque was positioned eccentrically with its posterior edge aligned with the posterior tumor margin to reduce the radiation dose to the optic disk and fovea. A minimal scleral dose sufficient to cause visible choroidal atrophy provided a permanent ophthalmoscopic record of the distribution of choroidal irradiation. If radiotherapy to the posterior tumor was uncertain, adjunctive transpupillary thermotherapy was administered 6 months postoperatively. Results The actuarial rates of tumor recurrence were 1%, 2%, and 3% at 2, 5, and 7 years, respectively. Local tumor recurrence correlated with the longest basal tumor dimension (Cox univariate analysis, p = 0.02, risk ratio 1.41, 95% confidence interval 1.06-1.88). Seven of the nine eyes with recurrent tumor were salvaged with additional conservative therapy. Conclusion The low rate of local tumor recurrence suggests that ruthenium plaque radiotherapy is effective with good case selection and if special measures are taken to ensure that the plaque is positioned correctly.

  18. Dose heterogeneity correction for low-energy brachytherapy sources using dual-energy CT images.

    PubMed

    Mashouf, S; Lechtman, E; Lai, P; Keller, B M; Karotki, A; Beachey, D J; Pignol, J P

    2014-09-21

    Permanent seed implant brachytherapy is currently used for adjuvant radiotherapy of early stage prostate and breast cancer patients. The current standard for calculation of dose around brachytherapy sources is based on the AAPM TG-43 formalism, which generates the dose in a homogeneous water medium. Recently, AAPM TG-186 emphasized the importance of accounting for tissue heterogeneities. We have previously reported on a methodology where the absorbed dose in tissue can be obtained by multiplying the dose, calculated by the TG-43 formalism, by an inhomogeneity correction factor (ICF). In this work we make use of dual energy CT (DECT) images to extract ICF parameters. The advantage of DECT over conventional CT is that it eliminates the need for tissue segmentation as well as assignment of population based atomic compositions. DECT images of a heterogeneous phantom were acquired and the dose was calculated using both TG-43 and TG-43 [Formula: see text] formalisms. The results were compared to experimental measurements using Gafchromic films in the mid-plane of the phantom. For a seed implant configuration of 8 seeds spaced 1.5 cm apart in a cubic structure, the gamma passing score for 2%/2 mm criteria improved from 40.8% to 90.5% when ICF was applied to TG-43 dose distributions.

  19. Three-Dimensional Imaging in Gynecologic Brachytherapy: A Survey of the American Brachytherapy Society

    SciTech Connect

    Viswanathan, Akila N.; Erickson, Beth A.

    2010-01-15

    Purpose: To determine current practice patterns with regard to three-dimensional (3D) imaging for gynecologic brachytherapy among American Brachytherapy Society (ABS) members. Methods and Materials: Registered physician members of the ABS received a 19-item survey by e-mail in August 2007. This report excludes physicians not performing brachytherapy for cervical cancer. Results: Of the 256 surveys sent, we report results for 133 respondents who perform one or more implantations per year for locally advanced cervical cancer. Ultrasound aids 56% of physicians with applicator insertion. After insertion, 70% of physicians routinely obtain a computed tomography (CT) scan. The majority (55%) use CT rather than X-ray films (43%) or magnetic resonance imaging (MRI; 2%) for dose specification to the cervix. However, 76% prescribe to Point A alone instead of using a 3D-derived tumor volume (14%), both Point A and tumor volume (7%), or mg/h (3%). Those using 3D imaging routinely contour the bladder and rectum (94%), sigmoid (45%), small bowel (38%), and/or urethra (8%) and calculate normal tissue dose-volume histogram (DVH) analysis parameters including the D2cc (49%), D1cc (36%), D0.1cc (19%), and/or D5cc (19%). Respondents most commonly modify the treatment plan based on International Commission on Radiation Units bladder and/or rectal point dose values (53%) compared with DVH values (45%) or both (2%). Conclusions: More ABS physician members use CT postimplantation imaging than plain films for visualizing the gynecologic brachytherapy apparatus. However, the majority prescribe to Point A rather than using 3D image based dosimetry. Use of 3D image-based treatment planning for gynecologic brachytherapy has the potential for significant growth in the United States.

  20. Recent developments and best practice in brachytherapy treatment planning

    PubMed Central

    2014-01-01

    Brachytherapy has evolved over many decades, but more recently, there have been significant changes in the way that brachytherapy is used for different treatment sites. This has been due to the development of new, technologically advanced computer planning systems and treatment delivery techniques. Modern, three-dimensional (3D) imaging modalities have been incorporated into treatment planning methods, allowing full 3D dose distributions to be computed. Treatment techniques involving online planning have emerged, allowing dose distributions to be calculated and updated in real time based on the actual clinical situation. In the case of early stage breast cancer treatment, for example, electronic brachytherapy treatment techniques are being used in which the radiation dose is delivered during the same procedure as the surgery. There have also been significant advances in treatment applicator design, which allow the use of modern 3D imaging techniques for planning, and manufacturers have begun to implement new dose calculation algorithms that will correct for applicator shielding and tissue inhomogeneities. This article aims to review the recent developments and best practice in brachytherapy techniques and treatments. It will look at how imaging developments have been incorporated into current brachytherapy treatment and how these developments have played an integral role in the modern brachytherapy era. The planning requirements for different treatments sites are reviewed as well as the future developments of brachytherapy in radiobiology and treatment planning dose calculation. PMID:24734939

  1. Multihelix rotating shield brachytherapy for cervical cancer

    SciTech Connect

    Dadkhah, Hossein; Kim, Yusung; Flynn, Ryan T.; Wu, Xiaodong

    2015-11-15

    Purpose: To present a novel brachytherapy technique, called multihelix rotating shield brachytherapy (H-RSBT), for the precise angular and linear positioning of a partial shield in a curved applicator. H-RSBT mechanically enables the dose delivery using only linear translational motion of the radiation source/shield combination. The previously proposed approach of serial rotating shield brachytherapy (S-RSBT), in which the partial shield is rotated to several angular positions at each source dwell position [W. Yang et al., “Rotating-shield brachytherapy for cervical cancer,” Phys. Med. Biol. 58, 3931–3941 (2013)], is mechanically challenging to implement in a curved applicator, and H-RSBT is proposed as a feasible solution. Methods: A Henschke-type applicator, designed for an electronic brachytherapy source (Xoft Axxent™) and a 0.5 mm thick tungsten partial shield with 180° or 45° azimuthal emission angles and 116° asymmetric zenith angle, is proposed. The interior wall of the applicator contains six evenly spaced helical keyways that rigidly define the emission direction of the partial radiation shield as a function of depth in the applicator. The shield contains three uniformly distributed protruding keys on its exterior wall and is attached to the source such that it rotates freely, thus longitudinal translational motion of the source is transferred to rotational motion of the shield. S-RSBT and H-RSBT treatment plans with 180° and 45° azimuthal emission angles were generated for five cervical cancer patients with a diverse range of high-risk target volume (HR-CTV) shapes and applicator positions. For each patient, the total number of emission angles was held nearly constant for S-RSBT and H-RSBT by using dwell positions separated by 5 and 1.7 mm, respectively, and emission directions separated by 22.5° and 60°, respectively. Treatment delivery time and tumor coverage (D{sub 90} of HR-CTV) were the two metrics used as the basis for evaluation and

  2. Multihelix rotating shield brachytherapy for cervical cancer

    PubMed Central

    Dadkhah, Hossein; Kim, Yusung; Wu, Xiaodong; Flynn, Ryan T.

    2015-01-01

    Purpose: To present a novel brachytherapy technique, called multihelix rotating shield brachytherapy (H-RSBT), for the precise angular and linear positioning of a partial shield in a curved applicator. H-RSBT mechanically enables the dose delivery using only linear translational motion of the radiation source/shield combination. The previously proposed approach of serial rotating shield brachytherapy (S-RSBT), in which the partial shield is rotated to several angular positions at each source dwell position [W. Yang et al., “Rotating-shield brachytherapy for cervical cancer,” Phys. Med. Biol. 58, 3931–3941 (2013)], is mechanically challenging to implement in a curved applicator, and H-RSBT is proposed as a feasible solution. Methods: A Henschke-type applicator, designed for an electronic brachytherapy source (Xoft Axxent™) and a 0.5 mm thick tungsten partial shield with 180° or 45° azimuthal emission angles and 116° asymmetric zenith angle, is proposed. The interior wall of the applicator contains six evenly spaced helical keyways that rigidly define the emission direction of the partial radiation shield as a function of depth in the applicator. The shield contains three uniformly distributed protruding keys on its exterior wall and is attached to the source such that it rotates freely, thus longitudinal translational motion of the source is transferred to rotational motion of the shield. S-RSBT and H-RSBT treatment plans with 180° and 45° azimuthal emission angles were generated for five cervical cancer patients with a diverse range of high-risk target volume (HR-CTV) shapes and applicator positions. For each patient, the total number of emission angles was held nearly constant for S-RSBT and H-RSBT by using dwell positions separated by 5 and 1.7 mm, respectively, and emission directions separated by 22.5° and 60°, respectively. Treatment delivery time and tumor coverage (D90 of HR-CTV) were the two metrics used as the basis for evaluation and

  3. A Novel MRI Marker for Prostate Brachytherapy

    SciTech Connect

    Frank, Steven J. Stafford, R. Jason; Bankson, James A.; Li Chun; Swanson, David A.; Kudchadker, Rajat J.; Martirosyan, Karen S.

    2008-05-01

    Purpose: Magnetic resonance imaging (MRI) is the optimal imaging modality for the prostate and surrounding critical organ structures. However, on MRI, the titanium radioactive seeds used for brachytherapy appear as black holes (negative contrast) and cannot be accurately localized. We sought to develop an encapsulated contrast agent marker (ECAM) with high-signal intensity on MRI to permit accurate localization of radioactive seeds with MRI during and after prostate brachytherapy. Methods and Materials: We investigated several agents with paramagnetic and superparamagnetic properties. The agents were injected into titanium, acrylic, and glass seeds, which were linked together in various combinations and imaged with MRI. The agent with the greatest T1-weighted signal was tested further in a canine prostate and agarose phantom. Studies were performed on a 1.5-T clinical MRI scanner. Results: The cobalt-chloride complex contrast (C4) agent with stoichiometry (CoCl{sub 2}){sub 0.8}(C{sub 2}H{sub 5}NO{sub 2}){sub 0.2} had the greatest T1-weighted signal (positive contrast) with a relaxivity ratio >1 (r{sub 2}/r{sub 1} = 1.21 {+-} 0.29). Acrylic-titanium and glass-titanium seed strands were clearly visualized with the encapsulated contrast agent marker. Conclusion: We have developed a novel ECAM that permits positive identification of the radioactive seeds used for prostate brachytherapy on MRI. Preclinical in vitro phantom studies and in vivo canine studies are needed to further optimize MRI sequencing techniques to facilitate MRI-based dosimetry.

  4. [Pulsed-dose rate brachytherapy in cervical cancers: why, how?].

    PubMed

    Mazeron, R; Dumas, I; Martin, V; Martinetti, F; Benhabib-Boukhelif, W; Gensse, M-C; Chargari, C; Guemnie-Tafo, A; Haie-Méder, C

    2014-10-01

    The end of the production of 192 iridium wires terminates low dose rate brachytherapy and requires to move towards pulsed-dose rate or high-dose rate brachytherapy. In the case of gynecological cancers, technical alternatives exist, and many teams have already taken the step of pulsed-dose rate for scientific reasons. Using a projector source is indeed a prerequisite for 3D brachytherapy, which gradually installs as a standard treatment in the treatment of cervical cancers. For other centers, this change implies beyond investments in equipment and training, organizational consequences to ensure quality.

  5. Image-guided high-dose-rate brachytherapy in inoperable endometrial cancer

    PubMed Central

    Petsuksiri, J; Chansilpa, Y; Hoskin, P J

    2014-01-01

    Inoperable endometrial cancer may be treated with curative aim using radical radiotherapy alone. The radiation techniques are external beam radiotherapy (EBRT) alone, EBRT plus brachytherapy and brachytherapy alone. Recently, high-dose-rate brachytherapy has been used instead of low-dose-rate brachytherapy. Image-guided brachytherapy enables sufficient coverage of tumour and reduction of dose to the organs at risk, thus increasing the therapeutic ratio of treatment. Local control rates with three-dimensional brachytherapy appear better than with conventional techniques (about 90–100% and 70–90%, respectively). PMID:24807067

  6. Dosimetric characterization and output verification for conical brachytherapy surface applicators. Part I. Electronic brachytherapy source

    PubMed Central

    Fulkerson, Regina K.; Micka, John A.; DeWerd, Larry A.

    2014-01-01

    Purpose: Historically, treatment of malignant surface lesions has been achieved with linear accelerator based electron beams or superficial x-ray beams. Recent developments in the field of brachytherapy now allow for the treatment of surface lesions with specialized conical applicators placed directly on the lesion. Applicators are available for use with high dose rate (HDR) 192Ir sources, as well as electronic brachytherapy sources. Part I of this paper will discuss the applicators used with electronic brachytherapy sources; Part II will discuss those used with HDR 192Ir sources. Although the use of these applicators has gained in popularity, the dosimetric characteristics including depth dose and surface dose distributions have not been independently verified. Additionally, there is no recognized method of output verification for quality assurance procedures with applicators like these. Existing dosimetry protocols available from the AAPM bookend the cross-over characteristics of a traditional brachytherapy source (as described by Task Group 43) being implemented as a low-energy superficial x-ray beam (as described by Task Group 61) as observed with the surface applicators of interest. Methods: This work aims to create a cohesive method of output verification that can be used to determine the dose at the treatment surface as part of a quality assurance/commissioning process for surface applicators used with HDR electronic brachytherapy sources (Part I) and 192Ir sources (Part II). Air-kerma rate measurements for the electronic brachytherapy sources were completed with an Attix Free-Air Chamber, as well as several models of small-volume ionization chambers to obtain an air-kerma rate at the treatment surface for each applicator. Correction factors were calculated using MCNP5 and EGSnrc Monte Carlo codes in order to determine an applicator-specific absorbed dose to water at the treatment surface from the measured air-kerma rate. Additionally, relative dose

  7. Improving photoacoustic imaging contrast of brachytherapy seeds

    NASA Astrophysics Data System (ADS)

    Pan, Leo; Baghani, Ali; Rohling, Robert; Abolmaesumi, Purang; Salcudean, Septimiu; Tang, Shuo

    2013-03-01

    Prostate brachytherapy is a form of radiotherapy for treating prostate cancer where the radiation sources are seeds inserted into the prostate. Accurate localization of seeds during prostate brachytherapy is essential to the success of intraoperative treatment planning. The current standard modality used in intraoperative seeds localization is transrectal ultrasound. Transrectal ultrasound, however, suffers in image quality due to several factors such speckle, shadowing, and off-axis seed orientation. Photoacoustic imaging, based on the photoacoustic phenomenon, is an emerging imaging modality. The contrast generating mechanism in photoacoustic imaging is optical absorption that is fundamentally different from conventional B-mode ultrasound which depicts changes in acoustic impedance. A photoacoustic imaging system is developed using a commercial ultrasound system. To improve imaging contrast and depth penetration, absorption enhancing coating is applied to the seeds. In comparison to bare seeds, approximately 18.5 dB increase in signal-to-noise ratio as well as a doubling of imaging depth are achieved. Our results demonstrate that the coating of the seeds can further improve the discernibility of the seeds.

  8. Fast GPU-based Monte Carlo simulations for LDR prostate brachytherapy

    NASA Astrophysics Data System (ADS)

    Bonenfant, Éric; Magnoux, Vincent; Hissoiny, Sami; Ozell, Benoît; Beaulieu, Luc; Després, Philippe

    2015-07-01

    The aim of this study was to evaluate the potential of bGPUMCD, a Monte Carlo algorithm executed on Graphics Processing Units (GPUs), for fast dose calculations in permanent prostate implant dosimetry. It also aimed to validate a low dose rate brachytherapy source in terms of TG-43 metrics and to use this source to compute dose distributions for permanent prostate implant in very short times. The physics of bGPUMCD was reviewed and extended to include Rayleigh scattering and fluorescence from photoelectric interactions for all materials involved. The radial and anisotropy functions were obtained for the Nucletron SelectSeed in TG-43 conditions. These functions were compared to those found in the MD Anderson Imaging and Radiation Oncology Core brachytherapy source registry which are considered the TG-43 reference values. After appropriate calibration of the source, permanent prostate implant dose distributions were calculated for four patients and compared to an already validated Geant4 algorithm. The radial function calculated from bGPUMCD showed excellent agreement (differences within 1.3%) with TG-43 accepted values. The anisotropy functions at r = 1 cm and r = 4 cm were within 2% of TG-43 values for angles over 17.5°. For permanent prostate implants, Monte Carlo-based dose distributions with a statistical uncertainty of 1% or less for the target volume were obtained in 30 s or less for 1 × 1 × 1 mm3 calculation grids. Dosimetric indices were very similar (within 2.7%) to those obtained with a validated, independent Monte Carlo code (Geant4) performing the calculations for the same cases in a much longer time (tens of minutes to more than a hour). bGPUMCD is a promising code that lets envision the use of Monte Carlo techniques in a clinical environment, with sub-minute execution times on a standard workstation. Future work will explore the use of this code with an inverse planning method to provide a complete Monte Carlo-based planning solution.

  9. Fast GPU-based Monte Carlo simulations for LDR prostate brachytherapy.

    PubMed

    Bonenfant, Éric; Magnoux, Vincent; Hissoiny, Sami; Ozell, Benoît; Beaulieu, Luc; Després, Philippe

    2015-07-07

    The aim of this study was to evaluate the potential of bGPUMCD, a Monte Carlo algorithm executed on Graphics Processing Units (GPUs), for fast dose calculations in permanent prostate implant dosimetry. It also aimed to validate a low dose rate brachytherapy source in terms of TG-43 metrics and to use this source to compute dose distributions for permanent prostate implant in very short times. The physics of bGPUMCD was reviewed and extended to include Rayleigh scattering and fluorescence from photoelectric interactions for all materials involved. The radial and anisotropy functions were obtained for the Nucletron SelectSeed in TG-43 conditions. These functions were compared to those found in the MD Anderson Imaging and Radiation Oncology Core brachytherapy source registry which are considered the TG-43 reference values. After appropriate calibration of the source, permanent prostate implant dose distributions were calculated for four patients and compared to an already validated Geant4 algorithm. The radial function calculated from bGPUMCD showed excellent agreement (differences within 1.3%) with TG-43 accepted values. The anisotropy functions at r = 1 cm and r = 4 cm were within 2% of TG-43 values for angles over 17.5°. For permanent prostate implants, Monte Carlo-based dose distributions with a statistical uncertainty of 1% or less for the target volume were obtained in 30 s or less for 1 × 1 × 1 mm(3) calculation grids. Dosimetric indices were very similar (within 2.7%) to those obtained with a validated, independent Monte Carlo code (Geant4) performing the calculations for the same cases in a much longer time (tens of minutes to more than a hour). bGPUMCD is a promising code that lets envision the use of Monte Carlo techniques in a clinical environment, with sub-minute execution times on a standard workstation. Future work will explore the use of this code with an inverse planning method to provide a complete Monte Carlo-based planning solution.

  10. Image-Based Brachytherapy for the Treatment of Cervical Cancer

    SciTech Connect

    Harkenrider, Matthew M. Alite, Fiori; Silva, Scott R.; Small, William

    2015-07-15

    Cervical cancer is a disease that requires considerable multidisciplinary coordination of care and labor in order to maximize tumor control and survival while minimizing treatment-related toxicity. As with external beam radiation therapy, the use of advanced imaging and 3-dimensional treatment planning has generated a paradigm shift in the delivery of brachytherapy for the treatment of cervical cancer. The use of image-based brachytherapy, most commonly with magnetic resonance imaging (MRI), requires additional attention and effort by the treating physician to prescribe dose to the proper volume and account for adjacent organs at risk. This represents a dramatic change from the classic Manchester approach of orthogonal radiographic images and prescribing dose to point A. We reviewed the history and currently evolving data and recommendations for the clinical use of image-based brachytherapy with an emphasis on MRI-based brachytherapy.

  11. Brachytherapy in India – a long road ahead

    PubMed Central

    Mahantshetty, Umesh; Shrivastava, Shyamkishore

    2014-01-01

    Brachytherapy can play a very important role in the definitive cure by radiation therapy in India. However, except for in a handful of centres, the majority of hospitals use it only for intracavitary treatment. The most probable reasons for such are the lack of logistical resources in terms of trained personal and supporting staff, rather than lack of radiotherapy machines and equipment. In this article, the authors look into the various aspects of brachytherapy in India: from its beginning to present days. The authors point out the resources available, shortcomings, and some possible solutions to make use of brachytherapy more popular and effective. Apart from presenting a picture of the present scenario, the article pays attention to the positive signs of brachytherapy becoming more popular in the near future. PMID:25337139

  12. Adjuvant brachytherapy in the treatment of soft-tissue sarcomas.

    PubMed

    Crownover, R L; Marks, K E

    1999-06-01

    For many patients with STS, administering adjuvant radiation treatments in the form of interstitial brachytherapy provides an excellent alternative to a protracted course of EBRT. Ideal patients are those with intermediate- or high-grade tumors amenable to en bloc resection. Attractive features of this approach include an untainted pathologic specimen, expeditious completion of treatment, reduction in wound complications, and improved functional outcome. Brachytherapy can permit definitive reirradiation by tightly localizing the high dose radiation exposure. It is also useful in patients who are known to have or be at high risk of metastatic disease, for whom the rapid completion of local treatment allows systemic therapy to begin quickly. Introduction of HDR techniques has shifted the delivery of brachytherapy from inpatient solitary confinement to an outpatient setting. Early reports using HDR brachytherapy for treatment of adult and pediatric STS are quite encouraging. The clinical equivalence between hyperfractionated HDR schedules and traditional LDR techniques is gaining acceptance.

  13. Patient release criteria for low dose rate brachytherapy implants.

    PubMed

    Boyce, Dale E; Sheetz, Michael A

    2013-04-01

    A lack of consensus regarding a model governing the release of patients following sealed source brachytherapy has led to a set of patient release policies that vary from institution to institution. The U.S. Nuclear Regulatory Commission has issued regulatory guidance on patient release in NUREG 1556, Volume 9, Rev. 2, Appendix U, which allows calculation of release limits following implant brachytherapy. While the formalism presented in NUREG is meaningful for the calculation of release limits in the context of relatively high energy gamma emitters, it does not estimate accurately the effective dose equivalent for the common low dose rate brachytherapy sources Cs, I, and Pd. NUREG 1556 states that patient release may be based on patient-specific calculations as long as the calculation is documented. This work is intended to provide a format for patient-specific calculations to be used for the consideration of patients' release following the implantation of certain low dose rate brachytherapy isotopes.

  14. Electromagnetic tracking for treatment verification in interstitial brachytherapy

    PubMed Central

    Kellermeier, Markus; Tanderup, Kari

    2016-01-01

    Electromagnetic tracking (EMT) is used in several medical fields to determine the position and orientation of dedicated sensors, e.g., attached to surgical tools. Recently, EMT has been introduced to brachytherapy for implant reconstruction and error detection. The manuscript briefly summarizes the main issues of EMT and error detection in brachytherapy. The potential and complementarity of EMT as treatment verification technology will be discussed in relation to in vivo dosimetry and imaging. PMID:27895688

  15. [Edge effect and late thrombosis -- inevitable complications of vascular brachytherapy?].

    PubMed

    Schiele, T M; Staber, L; Kantlehner, R; Pöllinger, B; Dühmke, E; Theisen, K; Klauss, V

    2002-11-01

    Restenosis is the limiting entity after percutaneous coronary angioplasty. Vascular brachytherapy for the treatment of in-stent restenosis has been shown to reduce the repeat restenosis rate and the incidence of major adverse events in several randomized trials. Besides the beneficial effects, brachytherapy yielded some unwanted side effects. The development of new stenoses at the edges of the target lesion treated with radiation is termed edge effect. It occurs after afterloading brachytherapy as well as after implantation of radioactive stents. It is characterized by extensive intimal hyperplasia and negative remodeling. As contributing factors the axial dose fall-off, inherent to all radioactive sources, and the application of vessel wall trauma by angioplasty have been identified. The combination of both factors, by insufficient overlap of the radiation length over the injured vessel segment, has been referred to as geographic miss. It has been shown to be associated with a very high incidence of the edge effect. Avoidance of geographic miss is strongly recommended in vascular brachytherapy procedures. Late thrombosis after vascular brachytherapy is of multifactorial origin. It comprises platelet recruitment, fibrin deposition, disturbed vasomotion, non-healing dissection and stent malapposition predisposing to turbulent blood flow. The strongest predictors for late thrombosis are premature discontinuation of antiplatelet therapy and implantation of new stents during the brachytherapy procedure. With a consequent and prolonged antiplatelet therapy, the incidence of late thrombosis has been reduced to placebo levels. Edge effect and late thrombosis represent unwanted side effects of vascular brachytherapy. By means of a thorough treatment planning and prolonged antiplatelet therapy their incidences can be largely reduced. With regard to the very favorable net effect, they do not constitute relevant limitations of vascular brachytherapy.

  16. The evolution of computerized treatment planning for brachytherapy: American contributions

    PubMed Central

    Rivard, Mark J.

    2014-01-01

    Purpose To outline the evolution of computerized brachytherapy treatment planning in the United States through a review of technological developments and clinical practice refinements. Material and methods A literature review was performed and interviews were conducted with six participants in the development of computerized treatment planning for brachytherapy. Results Computerized brachytherapy treatment planning software was initially developed in the Physics Departments of New York's Memorial Hospital (by Nelson, Meurk and Balter), and Houston's M. D. Anderson Hospital (by Stovall and Shalek). These public-domain programs could be used by institutions with adequate computational resources; other clinics had access to them via Memorial's and Anderson's teletype-based computational services. Commercial brachytherapy treatment planning programs designed to run on smaller computers (Prowess, ROCS, MMS), were developed in the late 1980s and early 1990s. These systems brought interactive dosimetry into the clinic and surgical theatre. Conclusions Brachytherapy treatment planning has evolved from systems of rigid implant rules to individualized pre- and intra-operative treatment plans, and post-operative dosimetric assessments. Brachytherapy dose distributions were initially calculated on public domain programs on large regionally located computers. With the progression of computer miniaturization and increase in processor speeds, proprietary software was commercially developed for microcomputers that offered increased functionality and integration with clinical practice. PMID:25097560

  17. Poster — Thur Eve — 41: Considerations for Patients with Permanently Implant Radioactive Sources Requiring Unrelated Surgery

    SciTech Connect

    Basran, P. S; Beckham, WA; Baxter, P

    2014-08-15

    Permanent implant of sealed radioactive sources is an effective technique for treating cancer. Typically, the radioactive sources are implanted in and near the disease, depositing dose locally over several months. There may be instances where these patients must undergo unrelated surgical procedures when the radioactive material remains active enough to pose risks. This work explores these risks, discusses strategies to mitigate those risks, and describes a case study for a permanent I-125 prostate brachytherapy implant patient who developed colo-rectal cancer and required surgery 6 months after brachytherapy. The first consideration is identifying the risk from unwarranted radiation to the patient and staff before, during, and after the surgical procedure. The second is identifying the risk the surgical procedure may have on the efficacy of the brachytherapy implant. Finally, there are considerations for controlling for radioactive substances from a regulatory perspective. After these risks are defined, strategies to mitigate those risks are considered. These strategies may include applying the concepts of ALARA, the use of protective equipment and developing a best practice strategy with the operating room team. We summarize this experience with some guidelines: If the surgical procedure is near (ex: 5 cm) of the implant; and, the surgical intervention may dislodge radioisotopes enough to compromise treatment or introduces radiation safety risks; and, the radioisotope has not sufficiently decayed to background levels; and, the surgery cannot be postponed, then a detailed analysis of risk is advised.

  18. A review of the clinical experience in pulsed dose rate brachytherapy

    PubMed Central

    Balgobind, Brian V; Koedooder, Kees; Ordoñez Zúñiga, Diego; Dávila Fajardo, Raquel; Rasch, Coen R N

    2015-01-01

    Pulsed dose rate (PDR) brachytherapy is a treatment modality that combines physical advantages of high dose rate (HDR) brachytherapy with the radiobiological advantages of low dose rate brachytherapy. The aim of this review was to describe the effective clinical use of PDR brachytherapy worldwide in different tumour locations. We found 66 articles reporting on clinical PDR brachytherapy including the treatment procedure and outcome. Moreover, PDR brachytherapy has been applied in almost all tumour sites for which brachytherapy is indicated and with good local control and low toxicity. The main advantage of PDR is, because of the small pulse sizes used, the ability to spare normal tissue. In certain cases, HDR resembles PDR brachytherapy by the use of multifractionated low-fraction dose. PMID:26290399

  19. A review of the clinical experience in pulsed dose rate brachytherapy.

    PubMed

    Balgobind, Brian V; Koedooder, Kees; Ordoñez Zúñiga, Diego; Dávila Fajardo, Raquel; Rasch, Coen R N; Pieters, Bradley R

    2015-01-01

    Pulsed dose rate (PDR) brachytherapy is a treatment modality that combines physical advantages of high dose rate (HDR) brachytherapy with the radiobiological advantages of low dose rate brachytherapy. The aim of this review was to describe the effective clinical use of PDR brachytherapy worldwide in different tumour locations. We found 66 articles reporting on clinical PDR brachytherapy including the treatment procedure and outcome. Moreover, PDR brachytherapy has been applied in almost all tumour sites for which brachytherapy is indicated and with good local control and low toxicity. The main advantage of PDR is, because of the small pulse sizes used, the ability to spare normal tissue. In certain cases, HDR resembles PDR brachytherapy by the use of multifractionated low-fraction dose.

  20. Variable Permanent Magnet Quadrupole

    SciTech Connect

    Mihara, T.; Iwashita, Y.; Kumada, M.; Spencer, C.M.; /SLAC

    2007-05-23

    A permanent magnet quadrupole (PMQ) is one of the candidates for the final focus lens in a linear collider. An over 120 T/m strong variable permanent magnet quadrupole is achieved by the introduction of saturated iron and a 'double ring structure'. A fabricated PMQ achieved 24 T integrated gradient with 20 mm bore diameter, 100 mm magnet diameter and 20 cm pole length. The strength of the PMQ is adjustable in 1.4 T steps, due to its 'double ring structure': the PMQ is split into two nested rings; the outer ring is sliced along the beam line into four parts and is rotated to change the strength. This paper describes the variable PMQ from fabrication to recent adjustments.

  1. Managing Permanent Objects

    DTIC Science & Technology

    1984-11-01

    sorage me hanism is the Chunk Management System ( CMS ). CMS provides a database-like interface for POMW. On first reference to a permanent object POMS...19] M.P. Atkinson, K.J. Chisholm, and W.P. Cockshott. CMS - A Chunk Management System . Technical Report CSR-110-82, Department of Computer Science...database manager . Creating and using emibedded systems is not always bad. In most large programming projets one ends up constructing and using some sort

  2. Permanent magnet design methodology

    NASA Technical Reports Server (NTRS)

    Leupold, Herbert A.

    1991-01-01

    Design techniques developed for the exploitation of high energy magnetically rigid materials such as Sm-Co and Nd-Fe-B have resulted in a revolution in kind rather than in degree in the design of a variety of electron guidance structures for ballistic and aerospace applications. Salient examples are listed. Several prototype models were developed. These structures are discussed in some detail: permanent magnet solenoids, transverse field sources, periodic structures, and very high field structures.

  3. Postoperative permanent pressure alopecia.

    PubMed

    Chang, Zi Yun; Ngian, Jan; Chong, Claudia; Chong, Chin Ted; Liew, Qui Yin

    2016-04-01

    A 49-year-old Chinese female underwent elective laparoscopic assisted Whipple's surgery lasting 12 h. This was complicated by postoperative pressure alopecia at the occipital area of the scalp. Pressure-induced hair loss after general anaesthesia is uncommon and typically temporary, but may be disconcerting to the patient. We report this case of postoperative permanent pressure alopecia due to its rarity in the anaesthesia/local literature, and review the risk factors for its development.

  4. Predictors of Metastatic Disease After Prostate Brachytherapy

    SciTech Connect

    Forsythe, Kevin; Burri, Ryan; Stone, Nelson; Stock, Richard G.

    2012-06-01

    Purpose: To identify predictors of metastatic disease after brachytherapy treatment for prostate cancer. Methods and Materials: All patients who received either brachytherapy alone (implant) or brachytherapy in combination with external beam radiation therapy for treatment of localized prostate cancer at The Mount Sinai Hospital between June 1990 and March 2007 with a minimum follow-up of 2 years were included. Univariate and multivariable analyses were performed on the following variables: risk group, Gleason score (GS), clinical T stage, pretreatment prostate-specific antigen level, post-treatment prostate-specific antigen doubling time (PSA-DT), treatment type (implant vs. implant plus external beam radiation therapy), treatment era, total biological effective dose, use of androgen deprivation therapy, age at diagnosis, and race. PSA-DT was analyzed in the following ordinate groups: 0 to 90 days, 91 to 180 days, 180 to 360 days, and greater than 360 days. Results: We included 1,887 patients in this study. Metastases developed in 47 of these patients. The 10-year freedom from distant metastasis (FFDM) rate for the entire population was 95.1%. Median follow-up was 6 years (range, 2-15 years). The only two significant predictors of metastatic disease by multivariable analyses were GS and PSA-DT (p < 0.001 for both variables). Estimated 10-year FFDM rates for GS of 6 or less, GS of 7, and GS of 8 or greater were 97.9%, 94.3%, and 76.1%, respectively (p < 0.001). Estimated FFDM rates for PSA-DT of 0 to 90 days, 91 to 180 days, 181 to 360 days, and greater than 360 days were 17.5%, 67.9%, 74%, and 94.8%, respectively (p < 0.001). Estimated 10-year FFDM rates for the low-, intermediate-, and high-risk groups were 98.6%, 96.2%, and 86.7%, respectively. A demographic shift to patients presenting with higher-grade disease in more recent years was observed. Conclusions: GS and post-treatment PSA-DT are both statistically significant independent predictors of metastatic

  5. Paddle-based rotating-shield brachytherapy

    PubMed Central

    Liu, Yunlong; Flynn, Ryan T.; Kim, Yusung; Dadkhah, Hossein; Bhatia, Sudershan K.; Buatti, John M.; Xu, Weiyu; Wu, Xiaodong

    2015-01-01

    Purpose: The authors present a novel paddle-based rotating-shield brachytherapy (P-RSBT) method, whose radiation-attenuating shields are formed with a multileaf collimator (MLC), consisting of retractable paddles, to achieve intensity modulation in high-dose-rate brachytherapy. Methods: Five cervical cancer patients using an intrauterine tandem applicator were considered to assess the potential benefit of the P-RSBT method. The P-RSBT source used was a 50 kV electronic brachytherapy source (Xoft Axxent™). The paddles can be retracted independently to form multiple emission windows around the source for radiation delivery. The MLC was assumed to be rotatable. P-RSBT treatment plans were generated using the asymmetric dose–volume optimization with smoothness control method [Liu et al., Med. Phys. 41(11), 111709 (11pp.) (2014)] with a delivery time constraint, different paddle sizes, and different rotation strides. The number of treatment fractions (fx) was assumed to be five. As brachytherapy is delivered as a boost for cervical cancer, the dose distribution for each case includes the dose from external beam radiotherapy as well, which is 45 Gy in 25 fx. The high-risk clinical target volume (HR-CTV) doses were escalated until the minimum dose to the hottest 2 cm3 (D2cm3) of either the rectum, sigmoid colon, or bladder reached their tolerance doses of 75, 75, and 90 Gy3, respectively, expressed as equivalent doses in 2 Gy fractions (EQD2 with α/β = 3 Gy). Results: P-RSBT outperformed the two other RSBT delivery techniques, single-shield RSBT (S-RSBT) and dynamic-shield RSBT (D-RSBT), with a properly selected paddle size. If the paddle size was angled at 60°, the average D90 increases for the delivery plans by P-RSBT on the five cases, compared to S-RSBT, were 2.2, 8.3, 12.6, 11.9, and 9.1 Gy10, respectively, with delivery times of 10, 15, 20, 25, and 30 min/fx. The increases in HR-CTV D90, compared to D-RSBT, were 16.6, 12.9, 7.2, 3.7, and 1.7 Gy10

  6. Harmony search optimization for HDR prostate brachytherapy

    NASA Astrophysics Data System (ADS)

    Panchal, Aditya

    In high dose-rate (HDR) prostate brachytherapy, multiple catheters are inserted interstitially into the target volume. The process of treating the prostate involves calculating and determining the best dose distribution to the target and organs-at-risk by means of optimizing the time that the radioactive source dwells at specified positions within the catheters. It is the goal of this work to investigate the use of a new optimization algorithm, known as Harmony Search, in order to optimize dwell times for HDR prostate brachytherapy. The new algorithm was tested on 9 different patients and also compared with the genetic algorithm. Simulations were performed to determine the optimal value of the Harmony Search parameters. Finally, multithreading of the simulation was examined to determine potential benefits. First, a simulation environment was created using the Python programming language and the wxPython graphical interface toolkit, which was necessary to run repeated optimizations. DICOM RT data from Varian BrachyVision was parsed and used to obtain patient anatomy and HDR catheter information. Once the structures were indexed, the volume of each structure was determined and compared to the original volume calculated in BrachyVision for validation. Dose was calculated using the AAPM TG-43 point source model of the GammaMed 192Ir HDR source and was validated against Varian BrachyVision. A DVH-based objective function was created and used for the optimization simulation. Harmony Search and the genetic algorithm were implemented as optimization algorithms for the simulation and were compared against each other. The optimal values for Harmony Search parameters (Harmony Memory Size [HMS], Harmony Memory Considering Rate [HMCR], and Pitch Adjusting Rate [PAR]) were also determined. Lastly, the simulation was modified to use multiple threads of execution in order to achieve faster computational times. Experimental results show that the volume calculation that was

  7. An overview of interstitial brachytherapy and hyperthermia

    SciTech Connect

    Brandt, B.B.; Harney, J.

    1989-11-01

    Interstitial thermoradiotherapy, an experimental cancer treatment that combines interstitial radiation implants (brachytherapy) and interstitial hyperthermia, is in the early stages of investigation. In accordance with the procedure used in a current national trial protocol, a 60-minute hyperthermia treatment is administered after catheters are placed into the tumor area while the patient is under general anesthesia. This is immediately followed by loading of radioactive Iridium-192 seeds into the catheters for a defined period of time. Once the prescribed radiation dose is delivered, the radioactive sources are removed and a second, 60-minute hyperthermia treatment is administered. Clinical trials with hyperthermia in combination with radiation have increased in recent years. Nurses caring for these patients need to become more knowledgeable about this investigational therapy. This paper provides an overview of the biologic rationale for this therapy, as well as a description of the delivery method and clinical application. Specific related nursing interventions are defined in a nursing protocol.23 references.

  8. Paddle-based rotating-shield brachytherapy

    SciTech Connect

    Liu, Yunlong; Xu, Weiyu; Flynn, Ryan T.; Kim, Yusung; Bhatia, Sudershan K.; Buatti, John M.; Dadkhah, Hossein; Wu, Xiaodong

    2015-10-15

    Purpose: The authors present a novel paddle-based rotating-shield brachytherapy (P-RSBT) method, whose radiation-attenuating shields are formed with a multileaf collimator (MLC), consisting of retractable paddles, to achieve intensity modulation in high-dose-rate brachytherapy. Methods: Five cervical cancer patients using an intrauterine tandem applicator were considered to assess the potential benefit of the P-RSBT method. The P-RSBT source used was a 50 kV electronic brachytherapy source (Xoft Axxent™). The paddles can be retracted independently to form multiple emission windows around the source for radiation delivery. The MLC was assumed to be rotatable. P-RSBT treatment plans were generated using the asymmetric dose–volume optimization with smoothness control method [Liu et al., Med. Phys. 41(11), 111709 (11pp.) (2014)] with a delivery time constraint, different paddle sizes, and different rotation strides. The number of treatment fractions (fx) was assumed to be five. As brachytherapy is delivered as a boost for cervical cancer, the dose distribution for each case includes the dose from external beam radiotherapy as well, which is 45 Gy in 25 fx. The high-risk clinical target volume (HR-CTV) doses were escalated until the minimum dose to the hottest 2 cm{sup 3} (D{sub 2cm{sup 3}}) of either the rectum, sigmoid colon, or bladder reached their tolerance doses of 75, 75, and 90 Gy{sub 3}, respectively, expressed as equivalent doses in 2 Gy fractions (EQD2 with α/β = 3 Gy). Results: P-RSBT outperformed the two other RSBT delivery techniques, single-shield RSBT (S-RSBT) and dynamic-shield RSBT (D-RSBT), with a properly selected paddle size. If the paddle size was angled at 60°, the average D{sub 90} increases for the delivery plans by P-RSBT on the five cases, compared to S-RSBT, were 2.2, 8.3, 12.6, 11.9, and 9.1 Gy{sub 10}, respectively, with delivery times of 10, 15, 20, 25, and 30 min/fx. The increases in HR-CTV D{sub 90}, compared to D-RSBT, were 16

  9. Calibration of Photon Sources for Brachytherapy

    NASA Astrophysics Data System (ADS)

    Rijnders, Alex

    Source calibration has to be considered an essential part of the quality assurance program in a brachytherapy department. Not only it will ensure that the source strength value used for dose calculation agrees within some predetermined limits to the value stated on the source certificate, but also it will ensure traceability to international standards. At present calibration is most often still given in terms of reference air kerma rate, although calibration in terms of absorbed dose to water would be closer to the users interest. It can be expected that in a near future several standard laboratories will be able to offer this latter service, and dosimetry protocols will have to be adapted in this way. In-air measurement using ionization chambers (e.g. a Baldwin—Farmer ionization chamber for 192Ir high dose rate HDR or pulsed dose rate PDR sources) is still considered the method of choice for high energy source calibration, but because of their ease of use and reliability well type chambers are becoming more popular and are nowadays often recommended as the standard equipment. For low energy sources well type chambers are in practice the only equipment available for calibration. Care should be taken that the chamber is calibrated at the standard laboratory for the same source type and model as used in the clinic, and using the same measurement conditions and setup. Several standard laboratories have difficulties to provide these calibration facilities, especially for the low energy seed sources (125I and 103Pd). Should a user not be able to obtain properly calibrated equipment to verify the brachytherapy sources used in his department, then at least for sources that are replaced on a regular basis, a consistency check program should be set up to ensure a minimal level of quality control before these sources are used for patient treatment.

  10. Methods for prostate stabilization during transperineal LDR brachytherapy

    NASA Astrophysics Data System (ADS)

    Podder, Tarun; Sherman, Jason; Rubens, Deborah; Messing, Edward; Strang, John; Ng, Wan-Sing; Yu, Yan

    2008-03-01

    In traditional prostate brachytherapy procedures for a low-dose-rate (LDR) radiation seed implant, stabilizing needles are first inserted to provide some rigidity and support to the prostate. Ideally this will provide better seed placement and an overall improved treatment. However, there is much speculation regarding the effectiveness of using regular brachytherapy needles as stabilizers. In this study, we explored the efficacy of two types of needle geometries (regular brachytherapy needle and hooked needle) and several clinically feasible configurations of the stabilization needles. To understand and assess the prostate movement during seed implantation, we collected in vivo data from patients during actual brachytherapy procedures. In vitro experimentation with tissue-equivalent phantoms allowed us to further understand the mechanics behind prostate stabilization. We observed superior stabilization with the hooked needles compared to the regular brachytherapy needles (more than 40% in bilateral parallel needle configuration). Prostate movement was also reduced significantly when regular brachytherapy needles were in an angulated configuration as compared to the parallel configuration (more than 60%). When the hooked needles were angulated for stabilization, further reduction in prostate displacement was observed. In general, for convenience of dosimetric planning and to avoid needle collision, all needles are desired to be in a parallel configuration. In this configuration, hooked needles provide improved stabilization of the prostate. On the other hand, both regular and hooked needles appear to be equally effective in reducing prostate movement when they are in angulated configurations, which will be useful in seed implantation using a robotic system. We have developed nonlinear spring-damper model for the prostate movement which can be used for adapting dosimetric planning during brachytherapy as well as for developing more realistic haptic devices and

  11. A study of optimization techniques in HDR brachytherapy for the prostate

    NASA Astrophysics Data System (ADS)

    Pokharel, Ghana Shyam

    Several studies carried out thus far are in favor of dose escalation to the prostate gland to have better local control of the disease. But optimal way of delivery of higher doses of radiation therapy to the prostate without hurting neighboring critical structures is still debatable. In this study, we proposed that real time high dose rate (HDR) brachytherapy with highly efficient and effective optimization could be an alternative means of precise delivery of such higher doses. This approach of delivery eliminates the critical issues such as treatment setup uncertainties and target localization as in external beam radiation therapy. Likewise, dosimetry in HDR brachytherapy is not influenced by organ edema and potential source migration as in permanent interstitial implants. Moreover, the recent report of radiobiological parameters further strengthen the argument of using hypofractionated HDR brachytherapy for the management of prostate cancer. Firstly, we studied the essential features and requirements of real time HDR brachytherapy treatment planning system. Automating catheter reconstruction with fast editing tools, fast yet accurate dose engine, robust and fast optimization and evaluation engine are some of the essential requirements for such procedures. Moreover, in most of the cases we performed, treatment plan optimization took significant amount of time of overall procedure. So, making treatment plan optimization automatic or semi-automatic with sufficient speed and accuracy was the goal of the remaining part of the project. Secondly, we studied the role of optimization function and constraints in overall quality of optimized plan. We have studied the gradient based deterministic algorithm with dose volume histogram (DVH) and more conventional variance based objective functions for optimization. In this optimization strategy, the relative weight of particular objective in aggregate objective function signifies its importance with respect to other objectives

  12. Liquids with permanent porosity

    NASA Astrophysics Data System (ADS)

    Giri, Nicola; Del Pópolo, Mario G.; Melaugh, Gavin; Greenaway, Rebecca L.; Rätzke, Klaus; Koschine, Tönjes; Pison, Laure; Gomes, Margarida F. Costa; Cooper, Andrew I.; James, Stuart L.

    2015-11-01

    Porous solids such as zeolites and metal-organic frameworks are useful in molecular separation and in catalysis, but their solid nature can impose limitations. For example, liquid solvents, rather than porous solids, are the most mature technology for post-combustion capture of carbon dioxide because liquid circulation systems are more easily retrofitted to existing plants. Solid porous adsorbents offer major benefits, such as lower energy penalties in adsorption-desorption cycles, but they are difficult to implement in conventional flow processes. Materials that combine the properties of fluidity and permanent porosity could therefore offer technological advantages, but permanent porosity is not associated with conventional liquids. Here we report free-flowing liquids whose bulk properties are determined by their permanent porosity. To achieve this, we designed cage molecules that provide a well-defined pore space and that are highly soluble in solvents whose molecules are too large to enter the pores. The concentration of unoccupied cages can thus be around 500 times greater than in other molecular solutions that contain cavities, resulting in a marked change in bulk properties, such as an eightfold increase in the solubility of methane gas. Our results provide the basis for development of a new class of functional porous materials for chemical processes, and we present a one-step, multigram scale-up route for highly soluble ‘scrambled’ porous cages prepared from a mixture of commercially available reagents. The unifying design principle for these materials is the avoidance of functional groups that can penetrate into the molecular cage cavities.

  13. Permanent Turbidity-Standards

    PubMed Central

    Roessler, William G.; Brewer, Carl R.

    1967-01-01

    Permanent turbidity reference standards suitable for measurement of microbial suspensions were prepared by suspending finely divided titanium dioxide in aryl sulfonamide-formaldehyde or methylstyrene resins. Turbidities of these standards, adjusted to a useful range for microbiological and immunological studies, were compared with other reference standards in use today. Tube holders for a Coleman Photonephelometer and a Nepho-Colorimeter were modified to eliminate the water well and to allow use of optically standardized 10-, 16-, or 18-mm test tubes. The standards and the tube holders have been used satisfactorily for more than 12 years. Images Fig. 5 Fig. 6 PMID:6077410

  14. Permanence can be Defended.

    PubMed

    McGee, Andrew; Gardiner, Dale

    2017-03-01

    In donation after the circulatory-respiratory determination of death (DCDD), the dead donor rule requires that the donor be dead before organ procurement can proceed. Under the relevant limb of the Uniform Determination of Death Act 1981 (USA), a person is dead when the cessation of circulatory-respiratory function is 'irreversible'. Critics of current practice in DCDD have argued that the donor is not dead at the time organs are procured, and so the procurement of organs from these donors violates the dead donor rule. We offer a new argument here in defence of current DCDD practice, and, in particular, of the interpretation of the requirement of 'irreversibility' as permanence.

  15. Utilization and Outcomes of Breast Brachytherapy in Younger Women

    SciTech Connect

    Smith, Grace L.; Huo, Jinhai; Giordano, Sharon H.; Hunt, Kelly K.; Buchholz, Thomas A.; Smith, Benjamin D.

    2015-09-01

    Purpose: To directly compare (1) radiation treatment utilization patterns; (2) risks of subsequent mastectomy; and (3) costs of radiation treatment in patients treated with brachytherapy versus whole-breast irradiation (WBI), in a national, contemporary cohort of women with incident breast cancer, aged 64 years and younger. Methods and Materials: Using MarketScan health care claims data, we identified 45,884 invasive breast cancer patients (aged 18-64 years), treated from 2003 to 2010 with lumpectomy, followed by brachytherapy (n=3134) or whole-breast irradiation (n=42,750). We stratified patients into risk groups according to age (Age<50 vs Age≥50) and endocrine therapy status (Endocrine− vs Endocrine+). “Endocrine+” patients filled an endocrine therapy prescription within 1 year after lumpectomy. Pathologic hormone receptor status was not available in this dataset. In brachytherapy versus WBI patients, utilization trends and 5-year subsequent mastectomy risks were compared. Stratified, adjusted subsequent mastectomy risks were calculated using proportional hazards regression. Results: Brachytherapy utilization increased from 2003 to 2010: in patients Age<50, from 0.6% to 4.9%; patients Age≥50 from 2.2% to 11.3%; Endocrine− patients, 1.3% to 9.4%; Endocrine+ patients, 1.9% to 9.7%. Age influenced treatment selection more than endocrine status: 17% of brachytherapy patients were Age<50 versus 32% of WBI patients (P<.001); whereas 41% of brachytherapy patients were Endocrine–versus 44% of WBI patients (P=.003). Highest absolute 5-year subsequent mastectomy risks occurred in Endocrine−/Age<50 patients (24.4% after brachytherapy vs 9.0% after WBI (hazard ratio [HR] 2.18, 95% confidence interval [CI] 1.37-3.47); intermediate risks in Endocrine−/Age≥50 patients (8.6% vs 4.9%; HR 1.76, 95% CI 1.26-2.46); and lowest risks in Endocrine+ patients of any age: Endocrine+/Age<50 (5.5% vs 4.5%; HR 1.18, 95% CI 0.61-2.31); Endocrine+/Age≥50 (4.2% vs 2

  16. Utilization and Outcomes of Breast Brachytherapy in Younger Women

    PubMed Central

    Smith, Grace L; Huo, Jinhai; Giordano, Sharon H.; Hunt, Kelly K.; Buchholz, Thomas A; Smith, Benjamin D

    2015-01-01

    Background Breast brachytherapy after lumpectomy is controversial in younger patients, as effectiveness is unclear and selection criteria are debated. Methods Using MarketScan® healthcare claims data, we identified 45,884 invasive breast cancer patients (ages 18–64), treated from 2003–2010 with lumpectomy, followed by brachytherapy (n=3,134) or whole breast irradiation (WBI) (n=42,750). We stratified patients into risk groups, based on age (Age<50 vs. Age≥50) and endocrine therapy status (Endocrine− vs. Endocrine+). “Endocrine+” patients filled an endocrine therapy prescription within 1 year after lumpectomy. Pathologic hormone receptor status was not available in this dataset. In brachytherapy vs. WBI patients, utilization trends and 5-year subsequent mastectomy risks were compared. Stratified, adjusted subsequent mastectomy risks were calculated using proportional hazards regression. Results Brachytherapy utilization increased from 2003 to 2010: In patients Age<50, from 0.6% to 4.9%; patients Age≥50 from 2.2% to 11.3%; Endocrine− patients, 1.3% to 9.4%; Endocrine+ patients, 1.9% to 9.7%. Age influenced treatment selection more than endocrine status: 17% of brachytherapy patients were Age<50 vs. 32% of WBI patients (P<0.001); while 41% of brachytherapy patients were Endocrine- vs. 44% of WBI patients (P=0.003). Highest absolute 5-year subsequent mastectomy risks occurred in Endocrine−/Age<50 patients (24.4% after brachytherapy vs. 9.0% after WBI (Hazard ratio[HR]=2.18, 1.37–3.47); intermediate risks in Endocrine−/Age≥50 patients (8.6% vs. 4.9%; HR=1.76, 1.26–2.46); and lowest risks in Endocrine+ patients of any age: Endocrine+/Age<50 (5.5% vs. 4.5%; HR=1.18, 0.61–2.31); Endocrine+/Age≥50 (4.2% vs. 2.4%; HR=1.71, 1.16–2.51). Conclusion In this younger cohort, endocrine status was a valuable discriminatory factor predicting subsequent mastectomy risk after brachytherapy vs. WBI and therefore may be useful for selecting appropriate

  17. Online gamma-camera imaging of 103Pd seeds (OGIPS) for permanent breast seed implantation

    NASA Astrophysics Data System (ADS)

    Ravi, Ananth; Caldwell, Curtis B.; Keller, Brian M.; Reznik, Alla; Pignol, Jean-Philippe

    2007-09-01

    Permanent brachytherapy seed implantation is being investigated as a mode of accelerated partial breast irradiation for early stage breast cancer patients. Currently, the seeds are poorly visualized during the procedure making it difficult to perform a real-time correction of the implantation if required. The objective was to determine if a customized gamma-camera can accurately localize the seeds during implantation. Monte Carlo simulations of a CZT based gamma-camera were used to assess whether images of suitable quality could be derived by detecting the 21 keV photons emitted from 74 MBq 103Pd brachytherapy seeds. A hexagonal parallel hole collimator with a hole length of 38 mm, hole diameter of 1.2 mm and 0.2 mm septa, was modeled. The design of the gamma-camera was evaluated on a realistic model of the breast and three layers of the seed distribution (55 seeds) based on a pre-implantation CT treatment plan. The Monte Carlo simulations showed that the gamma-camera was able to localize the seeds with a maximum error of 2.0 mm, using only two views and 20 s of imaging. A gamma-camera can potentially be used as an intra-procedural image guidance system for quality assurance for permanent breast seed implantation.

  18. Cryogenic Permanent Magnet Undulators

    SciTech Connect

    Chavanne, J.; Lebec, G.; Penel, C.; Revol, F.; Kitegi, C.

    2010-06-23

    For an in-vacuum undulator operated at small gaps the permanent magnet material needs to be highly resistant to possible electron beam exposure. At room temperature, one generally uses Sm{sub 2}Co{sub 17} or high coercivity NdFeB magnets at the expense of a limited field performance. In a cryogenic permanent magnet undulator (CPMU), at a temperature of around 150 K, any NdFeB grade reveals a coercivity large enough to be radiation resistant. In particular, very high remanence NdFeB material can be used to build undulators with enhanced field and X-ray brilliance at high photon energy provided that the pre-baking of the undulator above 100 deg. C can be eliminated. The ESRF has developed a full scale 2 m long CPMU with a period of 18 mm. This prototype has been in operation on the ID6 test beamline since January 2008. A significant effort was put into the characterization of NdFeB material at low temperature, the development of dedicated magnetic measurement systems and cooling methods. The measured heat budget with beam is found to be larger than expected without compromising the smooth operation of the device. Leading on from this first experience, new CPMUs are currently being considered for the upgrade of the ESRF.

  19. egs_brachy: a versatile and fast Monte Carlo code for brachytherapy

    NASA Astrophysics Data System (ADS)

    Chamberland, Marc J. P.; Taylor, Randle E. P.; Rogers, D. W. O.; Thomson, Rowan M.

    2016-12-01

    egs_brachy is a versatile and fast Monte Carlo (MC) code for brachytherapy applications. It is based on the EGSnrc code system, enabling simulation of photons and electrons. Complex geometries are modelled using the EGSnrc C++ class library and egs_brachy includes a library of geometry models for many brachytherapy sources, in addition to eye plaques and applicators. Several simulation efficiency enhancing features are implemented in the code. egs_brachy is benchmarked by comparing TG-43 source parameters of three source models to previously published values. 3D dose distributions calculated with egs_brachy are also compared to ones obtained with the BrachyDose code. Well-defined simulations are used to characterize the effectiveness of many efficiency improving techniques, both as an indication of the usefulness of each technique and to find optimal strategies. Efficiencies and calculation times are characterized through single source simulations and simulations of idealized and typical treatments using various efficiency improving techniques. In general, egs_brachy shows agreement within uncertainties with previously published TG-43 source parameter values. 3D dose distributions from egs_brachy and BrachyDose agree at the sub-percent level. Efficiencies vary with radionuclide and source type, number of sources, phantom media, and voxel size. The combined effects of efficiency-improving techniques in egs_brachy lead to short calculation times: simulations approximating prostate and breast permanent implant (both with (2 mm)3 voxels) and eye plaque (with (1 mm)3 voxels) treatments take between 13 and 39 s, on a single 2.5 GHz Intel Xeon E5-2680 v3 processor core, to achieve 2% average statistical uncertainty on doses within the PTV. egs_brachy will be released as free and open source software to the research community.

  20. Prostate brachytherapy in patients with median lobe hyperplasia.

    PubMed

    Wallner, K; Smathers, S; Sutlief, S; Corman, J; Ellis, W

    2000-06-20

    Our aim was to document the technical and clinical course of prostate brachytherapy patients with radiographic evidence of median lobe hyperplasia (MLH). Eight patients with MLH were identified during our routine brachytherapy practice, representing 9% of the 87 brachytherapy patients treated during a 6-month period. No effort was made to avoid brachytherapy in patients noted to have MLH on diagnostic work-up. Cystoscopic evaluation was not routinely performed. Postimplant axial computed tomographic (CT) images of the prostate were obtained at 0.5 cm intervals. Preimplant urinary obstructive symptoms were quantified by the criteria of the American Urologic Association (AUA). Each patient was contacted during the writing of this report to update postimplant morbidity information. There was no apparent association between the degree of MLH and preimplant prostate volume or AUA score. Intraoperatively, we were able to visualize MLH by transrectal ultrasound and did not notice any particular difficulty placing sources in the MLH tissue or migration of sources out of the tissue. The prescription isodose covered from 81% to 99% of the postimplant CT-defined target volume, achieving adequate dose to the median lobe tissue in all patients. Two of the eight patients developed acute, postimplant urinary retention. The first patient required intermittent self-catheterization for 3 months and then resumed spontaneous urination. MLH does not appear to be a strong contraindication to prostate brachytherapy, and prophylactic resection of hypertrophic tissue in such patients is probably not warranted. Int. J. Cancer (Radiat. Oncol. Invest.) 90, 152-156 (2000).

  1. Percutaneous interstitial brachytherapy for adrenal metastasis: technical report.

    PubMed

    Kishi, Kazushi; Tamura, Shinji; Mabuchi, Yasushi; Sonomura, Tetsuo; Noda, Yasutaka; Nakai, Motoki; Sato, Morio; Ino, Kazuhiko; Yamanaka, Noboru

    2012-09-01

    We developed and evaluated the feasibility of a brachytherapy technique as a safe and effective treatment for adrenal metastasis. Adapting a paravertebral insertion technique in radiofrequency ablation of adrenal tumors, we developed an interstitial brachytherapy for adrenal metastasis achievable on an outpatient basis. Under local anesthesia and under X-ray CT guidance, brachytherapy applicator needles were percutaneously inserted into the target. A treatment plan was created to eradicate the tumor while preserving normal organs including the spinal cord and kidney. We applied this interstitial brachytherapy technique to two patients: one who developed adrenal metastasis as the third recurrence of uterine cervical cancer after reirradiation, and one who developed metachronous multiple metastases from malignant melanoma. The whole procedure was completed in 2.5 hours. There were no procedure-related or radiation-related early/late complications. FDG PET-CT images at two and three months after treatment showed absence of FDG uptake, and no recurrence of the adrenal tumor was observed for over seven months until expiration, and for six months until the present, respectively. This interventional interstitial brachytherapy procedure may be useful as a safe and eradicative treatment for adrenal metastasis.

  2. Brachytherapy in the treatment of recurrent aggressive falcine meningiomas.

    PubMed

    Abou Al-Shaar, Hussam; Almefty, Kaith K; Abolfotoh, Mohammad; Arvold, Nils D; Devlin, Phillip M; Reardon, David A; Loeffler, Jay S; Al-Mefty, Ossama

    2015-09-01

    Recurrent aggressive falcine meningiomas are uncommon tumors that recur despite receiving extensive surgery and radiation therapy (RT). We have utilized brachytherapy as a salvage treatment in two such patients with a unique implantation technique. Both patients had recurrence of WHO Grade II falcine meningiomas despite multiple prior surgical and RT treatments. Radioactive I-125 seeds were made into strands and sutured into a mesh implant, with 1 cm spacing, in a size appropriate to cover the cavity and region of susceptible falcine dura. Following resection the vicryl mesh was implanted and fixed to the margins of the falx. Implantation in this interhemispheric space provides good dose conformality with targeting of at-risk tissue and minimal radiation exposure to normal neural tissues. The patients are recurrence free 31 and 10 months after brachytherapy treatment. Brachytherapy was an effective salvage treatment for the recurrent aggressive falcine meningiomas in our two patients.

  3. p-type silicon detector for brachytherapy dosimetry.

    PubMed

    Piermattei, A; Azario, L; Monaco, G; Soriani, A; Arcovito, G

    1995-06-01

    The sensitivity of a cylindrical p-type silicon detector was studied by means of air and water measurements using different photon beams. A lead filter cap around the diode was used to minimize the dependence of the detector response as a function of the brachytherapy photon energy. The radial dose distribution of a high-activity 192Ir source in a brachytherapy phantom was measured by means of the shielded diode and the agreement of these data with theoretical evaluations confirms the method used to compensate diode response in the intermediate energy range. The diode sensitivity was constant over a wide range of dose rates of clinical interest; this allowed one to have a small detector calibrated in terms of absorbed dose in a medium. Theoretical evaluations showed that a single shielding filter around the p-type diode is sufficient to obtain accurate dosimetry for 192Ir, 137Cs, and 60Co brachytherapy sources.

  4. Brachytherapy in the treatment of skin cancer: an overview

    PubMed Central

    2015-01-01

    The incidence of skin cancer worldwide is constantly growing and it is the most frequently diagnosed tumor. Brachytherapy (BT) in particular localizations is a valuable tool of the exact radiation depot inside the tumor mass. In localizations such as the face, skull skin and inoperable tumors, relapses after surgery, radiotherapy are usually not suitable for primary or secondary invasive treatment. Brachytherapy is a safe procedure for organs at risk according to rapid fall of a dose outside the axis of the applicator with satisfactory dose localization inside the target. The complications rate is acceptable and treatment costs are low. In some tumors (great skin lesions in the scalp, near eyes or on the nose) BT allows for a great dose reduction in surrounding healthy tissues. Brachytherapy provides minimal dose delivery to surrounding healthy tissue, thus enabling good functional and cosmetic results. Treatment is possible almost in all cases on an outpatient basis. PMID:26759545

  5. SU-E-T-378: Evaluation of An Analytical Model for the Inter-Seed Attenuation Effect in 103-Pd Multi-Seed Implant Brachytherapy

    SciTech Connect

    Safigholi, H; Soliman, A; Song, W; Meigooni, A Soleimani; Han, D

    2015-06-15

    Purpose: Brachytherapy treatment planning systems based on TG-43 protocol calculate the dose in water and neglects the heterogeneity effect of seeds in multi-seed implant brachytherapy. In this research, the accuracy of a novel analytical model that we propose for the inter-seed attenuation effect (ISA) for 103-Pd seed model is evaluated. Methods: In the analytical model, dose perturbation due to the ISA effect for each seed in an LDR multi-seed implant for 103-Pd is calculated by assuming that the seed of interest is active and the other surrounding seeds are inactive. The cumulative dosimetric effect of all seeds is then summed using the superposition principle. The model is based on pre Monte Carlo (MC) simulated 3D kernels of the dose perturbations caused by the ISA effect. The cumulative ISA effect due to multiple surrounding seeds is obtained by a simple multiplication of the individual ISA effect by each seed, the effect of which is determined by the distance from the seed of interest. This novel algorithm is then compared with full MC water-based simulations (FMCW). Results: The results show that the dose perturbation model we propose is in excellent agreement with the FMCW values for a case with three seeds separated by 1 cm. The average difference of the model and the FMCW simulations was less than 8%±2%. Conclusion: Using the proposed novel analytical ISA effect model, one could expedite the corrections due to the ISA dose perturbation effects during permanent seed 103-Pd brachytherapy planning with minimal increase in time since the model is based on multiplications and superposition. This model can be applied, in principle, to any other brachytherapy seeds. Further work is necessary to validate this model on a more complicated geometry as well.

  6. Achieving permanency for LGBTQ youth.

    PubMed

    Jacobs, Jill; Freundlich, Madelyn

    2006-01-01

    This article brings together two significant efforts in the child welfare field: achieving permanence for youth in out-of-home care and meeting the needs of lesbian, gay, bisexual, transgender and questioning (LGBTQ) youth. During the past several years, a national movement has taken place to assure all children and youth have a permanent family connection before leaving the child welfare system; however, LGBTQ youth are not routinely included in the permanency discussions. At the same time, efforts in addressing the needs of LGBTQ youth have increased, but permanency is rarely mentioned as a need. This article offers models of permanence and practices to facilitate permanence with LGBTQ youth and their families. It also offers a youth-driven, individualized process, using youth development principles to achieve relational, physical, and legal permanence. Reunification efforts are discussed, including services, supports, and education required for youth to return to their family of origin. For those who cannot return home, other family resources are explored. The article also discusses cultural issues as they affect permanence for LGBTQ youth, and, finally, addresses the need for ongoing support services to sustain and support permanency.

  7. Current state of the art brachytherapy treatment planning dosimetry algorithms

    PubMed Central

    Pantelis, E; Karaiskos, P

    2014-01-01

    Following literature contributions delineating the deficiencies introduced by the approximations of conventional brachytherapy dosimetry, different model-based dosimetry algorithms have been incorporated into commercial systems for 192Ir brachytherapy treatment planning. The calculation settings of these algorithms are pre-configured according to criteria established by their developers for optimizing computation speed vs accuracy. Their clinical use is hence straightforward. A basic understanding of these algorithms and their limitations is essential, however, for commissioning; detecting differences from conventional algorithms; explaining their origin; assessing their impact; and maintaining global uniformity of clinical practice. PMID:25027247

  8. Imaging method for monitoring delivery of high dose rate brachytherapy

    DOEpatents

    Weisenberger, Andrew G; Majewski, Stanislaw

    2012-10-23

    A method for in-situ monitoring both the balloon/cavity and the radioactive source in brachytherapy treatment utilizing using at least one pair of miniature gamma cameras to acquire separate images of: 1) the radioactive source as it is moved in the tumor volume during brachytherapy; and 2) a relatively low intensity radiation source produced by either an injected radiopharmaceutical rendering cancerous tissue visible or from a radioactive solution filling a balloon surgically implanted into the cavity formed by the surgical resection of a tumor.

  9. [Guidelines for external radiotherapy and brachytherapy: 2nd edition].

    PubMed

    Mahé, M-A; Barillot, I; Chauvet, B

    2016-09-01

    In 2007, a first edition was published with the objective to produce guidelines for optimization, harmonization and homogenization of practices in external radiation therapy in France. The second edition, including brachytherapy, has the same objective and takes into account recent technologic improvements (intensity modulation radiation therapy, stereotactic radiotherapy, and 3-dimension brachytherapy) and results of literature. The first part is about daily use of general principles (quality, security, image-guided radiation therapy) and the second is to describe each treatment step in main cancers.

  10. Dosimetry of two new interstitial brachytherapy sources

    NASA Astrophysics Data System (ADS)

    Saidi, Pooneh; Sadeghi, Mahdi

    2011-01-01

    With increased demand for low 103Pd (palladium) seed sources, to treat prostate and eye cancers, new sources have been designed and introduced. This article presents the two new palladium brachytherapy sources, IR03-103Pd and IR04-103Pd that have been developed at Nuclear Science and Technology Research Institute. The dosimetry parameters such as the dose rate constant Λ, the radial dose function g(r), and the anisotropy function F(r,θ), around the sources have been characterized using Version 5 Monte Carlo radiation transport code in accordance with the update AAPM Task Group No. 43 report (TG-43U1). The results indicated the dose rate constant of 0.689±0.02 and 0.667±0.02 cGy h-1 U-1 for the IR03-103Pd and IR04-103Pd sources respectively, which are in acceptable agreement with other commercial seeds. The calculated results were compared with published results for those of other source manufacturers. However, they show an acceptable dose distribution, using for clinical applications is pending experimental dosimetry.

  11. Radiotherapy and brachytherapy for recurrent colorectal cancer

    SciTech Connect

    Nag, S. )

    1991-05-01

    Radical surgical excision of locoregional recurrence of colorectal carcinoma usually produces the best survival and should be attempted whenever possible. However, recurrences are often unresectable; hence palliative local therapy may be indicated. There are several options for the radiation therapy of local, unresectable, recurrent, or metastatic colorectal cancer. Whole pelvis irradiation of 4,000-5,000 cGy followed by a coned-down boost of 1,000-1,500 cGy generally provides good symptomatic palliation in 80-90% of patients, but long-term control or cure is rarely achieved. External beam irradiation of 2,000-3,000 cGy to the whole liver with or without concurrent chemotherapy may be used for palliation of metastatic disease to the liver. A combination of intraoperative radiation therapy applied directly to the tumor bed and external beam irradiation may improve local control and survival rates. Multiple options are available for the intraoperative use of brachytherapy which can deliver high radiation doses to the residual tumor, or tumor bed, sparing normal tissue.

  12. Epimacular brachytherapy for wet AMD: current perspectives

    PubMed Central

    Casaroli-Marano, Ricardo P; Alforja, Socorro; Giralt, Joan; Farah, Michel E

    2014-01-01

    Age-related macular degeneration (AMD) is considered the most common cause of blindness in the over-60 age group in developed countries. There are basically two forms of presentation: geographic (dry or atrophic) and wet (neovascular or exudative). Geographic atrophy accounts for approximately 85%–90% of ophthalmic frames and leads to a progressive degeneration of the retinal pigment epithelium and the photoreceptors. Wet AMD causes the highest percentage of central vision loss secondary to disease. This neovascular form involves an angiogenic process in which newly formed choroidal vessels invade the macular area. Today, intravitreal anti-angiogenic drugs attempt to block the angiogenic events and represent a major advance in the treatment of wet AMD. Currently, combination therapy for wet AMD includes different forms of radiation delivery. Epimacular brachytherapy (EMBT) seems to be a useful approach to be associated with current anti-vascular endothelial growth factor agents, presenting an acceptable efficacy and safety profile. However, at the present stage of research, the results of the clinical trials carried out to date are insufficient to justify extending routine use of EMBT for the treatment of wet AMD. PMID:25210436

  13. Epimacular brachytherapy for wet AMD: current perspectives.

    PubMed

    Casaroli-Marano, Ricardo P; Alforja, Socorro; Giralt, Joan; Farah, Michel E

    2014-01-01

    Age-related macular degeneration (AMD) is considered the most common cause of blindness in the over-60 age group in developed countries. There are basically two forms of presentation: geographic (dry or atrophic) and wet (neovascular or exudative). Geographic atrophy accounts for approximately 85%-90% of ophthalmic frames and leads to a progressive degeneration of the retinal pigment epithelium and the photoreceptors. Wet AMD causes the highest percentage of central vision loss secondary to disease. This neovascular form involves an angiogenic process in which newly formed choroidal vessels invade the macular area. Today, intravitreal anti-angiogenic drugs attempt to block the angiogenic events and represent a major advance in the treatment of wet AMD. Currently, combination therapy for wet AMD includes different forms of radiation delivery. Epimacular brachytherapy (EMBT) seems to be a useful approach to be associated with current anti-vascular endothelial growth factor agents, presenting an acceptable efficacy and safety profile. However, at the present stage of research, the results of the clinical trials carried out to date are insufficient to justify extending routine use of EMBT for the treatment of wet AMD.

  14. Diagnostic methods for deep vein thrombosis: venous Doppler examination, phleborheography, iodine-125 fibrinogen uptake, and phlebography

    SciTech Connect

    Comerota, A.J.; White, J.V.; Katz, M.L.

    1985-10-08

    Since clinical diagnosis of DVT is often inaccurate, it has become accepted that an objective means of diagnosing clot in the deep venous system becomes critically important in the management of these patients. The venous Doppler examination monitors the velocity of blood flowing through a particular vein. Doppler probes in the 5 to 10 mHz range are routinely used. Respiratory variation is a normal finding due to a diminished flow signal during inspiration, followed by a progressive increase in flow signal during expiration. Characteristics of the spontaneous flow signals are the most important part of interpreting the venous Doppler examination. In addition, the response to distal or proximal compression (augmentation) adds important information to the interpretation; however, the response during any augmentation maneuver depends on the rapidity of compression, the force of compression, the quantity of blood in the veins at the time of compression, and the distance between the Doppler probe and the compression point. Phleborheography is a six-channel volumetric plethysmographic technique that monitors volume changes in the lower extremities associated with respiration and foot and calf compression.

  15. Quantitative analysis of myocardial kinetics of 15-p-(iodine-125) iodophenylpentadecanoic acid

    SciTech Connect

    DeGrado, T.R.; Holden, J.E.; Ng, C.K.; Raffel, D.M.; Gatley, S.J.

    1989-07-01

    Myocardial extraction and the characteristic tissue clearance of radioactivity following bolus injections of a radioiodinated (/sup 125/I) long chain fatty acid (LCFA) analog 15-p-iodophenylpentadecanoic acid (IPPA) were examined in the isolated perfused working rat heart. Radioactivity remaining in the heart was monitored with external scintillation probes. A compartmental model which included nonesterified tracer, catabolite, and complex lipid compartments successfully fitted tissue time-radioactivity residue curves, and gave a value for the rate of IPPA oxidation 1.8 times that obtained from steady-state release of tritiated water from labeled palmitic acid. The technique was sensitive to the impairment of LCFA oxidation in hearts of animals treated with the carnitine palmitoyltransferase I inhibitor, 2(5(4-chlorophenyl)pentyl)oxirane-2-carboxylate (POCA). IPPA or similar modified fatty acids may be better than /sup 11/C-labeled physiological fatty acids such as palmitate in this type of study, because efflux of unoxidized tracer and catabolite(s) from the heart are kinetically more distinct, and their contributions to the early data can be reliably separated. This technique may be suitable for extension to in vivo measurements with position tomography and appropriate modified fatty acids.

  16. Experience with interstitial implantation of iodine 125 in the treatment of prostatic carcinoma.

    PubMed

    Sogani, P C; Whitmore, W F; Hilaris, B S; Batata, M A

    1980-01-01

    Between February 1970 and April 1977 300 patients with localized prostatic carcinoma were treated with I-125 implantation and bilateral pelvic lymphadenectomy at Memorial Sloan-Kettering Cancer Center (MSKCC). 68% had clinical Stage B (T-1 and T-2) and 32% had Stage C (T-3) neoplasms. Pelvic lymph nodes were histologically positive in 38% of the patients. Five-year survival for all patients was 73%. Five-year survival for Stage B disease was 100% and Stage C 65%. Lymph node metastases implied a poor prognosis. While 92% of patients with negative nodes survived five years, only 46% of the patients with positive nodes did so. Supplemental external radiation to pelvic and periaortic region in 28 patients with positive nodes did not improve survival or disease free interval or reduce distal or local recurrence but rather increased the incidence of radiation morbidity. The complications and morbidity as a consequence of I-125 implantation are minimal. The ultimate role of I-125 implantation in the management of localized prostatic cancer is yet to be determined. The early experience with this technique, however, suggests that it may be as effective as alternative modalities for comparable stages in terms of patient survival and may prove superior in terms of the quality of survival.

  17. Ultrasonically guided percutaneous implantation of iodine-125 seeds in pancreatic carcinoma

    SciTech Connect

    Joyce, F.; Burcharth, F.; Holm, H.H.; Stroyer, I. )

    1990-10-01

    Cancer of the pancreas is most often not diagnosed before it has reached unresectable stages. The development of effective palliative treatment for these patients and for those with recurrence after resection is clearly needed. The present study reports the results of ultrasonically guided percutaneous implantation of {sup 125}I seeds in 19 patients with cancer of the pancreas. Twelve patients had further adjuvant external radiation. Despite satisfactory seed placement and delivery of the planned radiation dose in most cases, clinical improvement was lacking or only slight and short-lived. No difference in survival or palliation was observed between patients treated with seeds alone compared with patients treated with seeds and external radiation. Survival after seed implantation was short (median 140 days, range 7-401 days). Ultrasonically guided percutaneous implantation of {sup 125}I seeds cannot be recommended in the treatment of unresectable carcinoma of the pancreas.

  18. Dual isotope study of iodine-125 and indium-111-labeled antibody in athymic mice

    SciTech Connect

    Carney, P.L.; Rogers, P.E.; Johnson, D.K. )

    1989-03-01

    Monoclonal antibody B72.3 was coupled to a benzylisothiocyanate derivative of diethylenetriaminepentaacetic acid (DTPA). The maximum substitution achievable without loss of immunoreactivity was three DTPA groups per immunoglobulin molecule. The resulting conjugate was labeled with {sup 111}In by brief incubation with {sup 111}InCl{sub 3}, giving a mean radiochemical yield of {sup 111}In-labeled antibody of 96%. The ({sup 111}In)B72.3 preparation was mixed with an ({sup 125}I) B72.3 preparation, obtained by the chloramine-T method, and the mixture administered to athymic mice bearing subcutaneous LS174T colon carcinoma xenografts. There were no significant differences (p greater than 0.1) in the biodistributions of the two labels at 1, 2, 5, and 7 days postinjection. These results are contrasted with prior studies showing elevated levels of {sup 111}In in liver, spleen, and kidneys using B72.3-DTPA conjugates prepared via the bicyclic anhydride. It is concluded that protein cross-linking and/or the formation of unstable chelate sites in anhydride coupled conjugates underlie these disparities.

  19. Quantitative radiommunoassay for DNA-binding antibodies. [Iodine 131, Iodine 125

    SciTech Connect

    Smith, L.H.; Guyer, R.L.; Minami, R.M.; Teplitz, R.L.

    1981-09-01

    A radioimmunoassay (RIA) is described for the measurement of serum immunoglobulins capable of binding to double-standard or single-standard DNA. DNA attached to Sephadex G-50 by ultraviolet radiation was used as a solid- phase immunoabsorbent for DNA-binding proteins from serum. Goat anti-human (GAH) IgG (/sup 125/I-labeled) were used to detect the human immunoglobulins bound onto the washed DNA-Sephadex. The quantities of immunoglobulins bound were determined by comparison with a standard curve constructed by dilution of a plasma from an systemic lupus erythematosus (SLE) patient containing known amounts of bound, DNA-specific IgM and IgG. Another RIA was employed for measuring levels of IgG and IgM. In combination with measurements of the total serum IgM and IgG, the RIA allowed for the determination of the fraction of the total serum IgM or IgG that was specific for double- or single-standard DNA. For a pool of normal human sera the quantities were as follows: 0.04% of the total IgM and 0.001% of the total IgG bound double-standard DNA; 0.22% of the total IgM and 0.05% of the total IgG bound single-stranded DNA. This capability is important because information regarding the quantitative measurement of antibodies to DNA and their class determination may be of significance in monitoring the status of subjects with SLE.

  20. Auger-electron cascades, charge potential and microdosimetry of iodine-125.

    PubMed

    Booz, J; Paretzke, H G; Pomplun, E; Olko, P

    1987-01-01

    This paper is a contribution to the microdosimetry of I-125. It shows microdosimetric spectra of individual and average disintegrations of I-125 for various target sizes and gives evidence for the relative contributions of energy-deposition events of low and high LET. It further presents information on the relative efficiencies of Auger-electrons and multiple charges in terms of local energy deposition, e.g. to model targets of DNA, and discusses their radiobiological implications, e.g. the microdosimetric understanding of the different efficiencies of specific and random incorporations of I-125. When I-125 is specifically incorporated into DNA, most of the energy deposition events are very large, e.g. above 40 keV/micron for a simulated target volume of 20 nm diameter, regardless of the number and energy of Auger electrons emitted. Therefore it is not necessary, for the discussion of the radiobiological implications, to distinguish between different classes of disintegrations. For unspecific, homogeneous incorporation of I-125 somewhere into tissue, about 20% of the dose to critical targets of 25 nm diameter is made up by disintegrations that happen to occur within these targets. When assuming that other critical targets and target structures can be neglected, this part of the dose will be equally effective as in the case of specific incorporation of I-125 into such target models. In addition, there are the normal, low-LET radiation effects from the other, 80% large fraction of the dose. With this information, for the biological systems and end points for which a short section of the elemental chromatine fiber can be taken as the relevant critical target, it is shown that the expected D37 value for homogeneous unspecific incorporation of I-125 can be estimated when the D37 for specific incorporation in DNA is known. For an example calculation, the estimated D37-value for nonspecific, homogeneous incorporation of I-125 would be about half as effective as specifically incorporated I-125. Thus, the microdosimetric data of the present work show that a high efficiency of homogeneous incorporation of I-125 into the cell nucleus is not necessarily in contradiction with the idea of I-125 disintegrations inside the DNA being the main cause of radiation action.

  1. Postoperative interstitial brachytherapy in eyelid cancer: long term results and assessment of Cosmesis After Interstitial Brachytherapy scale

    PubMed Central

    Basu, Trinanjan; Chaudhary, Suresh; Chaukar, Devendra; Nadkarni, Mandar; GN, Manjunatha

    2014-01-01

    Purpose To analyse feasibility and safety of postoperative interstitial brachytherapy (IBRT) in patients of eyelid cancer treated primarily by surgical excision. Material and methods In this series, 8 patients with eyelid cancer were treated using postoperative interstitial brachytherapy. Patients were followed up for local control, cosmetic outcome, and acute and late toxicities. Cosmetic outcome was measured using a 6 point indigenous Cosmesis After Interstitial Brachytherapy (CAIB) scale. Results The patients were between 23-82 years (median: 71 years). There were 3 females and 5 males, and 3 patients had lesions in upper eyelid. Postoperative high-dose-rate brachytherapy was used in all with 2 catheters implanted in most of them (6 out of 8). Local control was calculated from end of treatment to last follow-up. At last follow-up, all patients remained locally controlled. Two patients had nodal recurrence 6 months after interstitial brachytherapy and were salvaged effectively by external beam radiotherapy. At last follow-up, 7 patients were loco-regionally controlled and one was lost to follow up. All patients had Radiation Therapy Oncology Group (RTOG) grade 1 acute toxicity and 2 had grade 1 Common Terminology Criteria for Adverse Events (CTCAE) version.3 late toxicities. The cosmesis score for the whole group ranged between 0-1 indicating excellent to very good cosmesis. Conclusions Postoperative high-dose-rate brachytherapy resulted in excellent disease control and cosmesis without significant acute or late toxicities. It is an effective modality for treatment of eyelid cancers in selected patients. Future prospective studies with the validation of CAIB scale would give us more insight to this effective yet often ignored modality of IBRT. PMID:25834578

  2. Patient-specific Monte Carlo dose calculations for 103Pd breast brachytherapy

    NASA Astrophysics Data System (ADS)

    Miksys, N.; Cygler, J. E.; Caudrelier, J. M.; Thomson, R. M.

    2016-04-01

    This work retrospectively investigates patient-specific Monte Carlo (MC) dose calculations for 103Pd permanent implant breast brachytherapy, exploring various necessary assumptions for deriving virtual patient models: post-implant CT image metallic artifact reduction (MAR), tissue assignment schemes (TAS), and elemental tissue compositions. Three MAR methods (thresholding, 3D median filter, virtual sinogram) are applied to CT images; resulting images are compared to each other and to uncorrected images. Virtual patient models are then derived by application of different TAS ranging from TG-186 basic recommendations (mixed adipose and gland tissue at uniform literature-derived density) to detailed schemes (segmented adipose and gland with CT-derived densities). For detailed schemes, alternate mass density segmentation thresholds between adipose and gland are considered. Several literature-derived elemental compositions for adipose, gland and skin are compared. MC models derived from uncorrected CT images can yield large errors in dose calculations especially when used with detailed TAS. Differences in MAR method result in large differences in local doses when variations in CT number cause differences in tissue assignment. Between different MAR models (same TAS), PTV {{D}90} and skin {{D}1~\\text{c{{\\text{m}}3}}} each vary by up to 6%. Basic TAS (mixed adipose/gland tissue) generally yield higher dose metrics than detailed segmented schemes: PTV {{D}90} and skin {{D}1~\\text{c{{\\text{m}}3}}} are higher by up to 13% and 9% respectively. Employing alternate adipose, gland and skin elemental compositions can cause variations in PTV {{D}90} of up to 11% and skin {{D}1~\\text{c{{\\text{m}}3}}} of up to 30%. Overall, AAPM TG-43 overestimates dose to the PTV ({{D}90} on average 10% and up to 27%) and underestimates dose to the skin ({{D}1~\\text{c{{\\text{m}}3}}} on average 29% and up to 48%) compared to the various MC models derived using the post-MAR CT images studied

  3. Patient-specific Monte Carlo dose calculations for (103)Pd breast brachytherapy.

    PubMed

    Miksys, N; Cygler, J E; Caudrelier, J M; Thomson, R M

    2016-04-07

    This work retrospectively investigates patient-specific Monte Carlo (MC) dose calculations for (103)Pd permanent implant breast brachytherapy, exploring various necessary assumptions for deriving virtual patient models: post-implant CT image metallic artifact reduction (MAR), tissue assignment schemes (TAS), and elemental tissue compositions. Three MAR methods (thresholding, 3D median filter, virtual sinogram) are applied to CT images; resulting images are compared to each other and to uncorrected images. Virtual patient models are then derived by application of different TAS ranging from TG-186 basic recommendations (mixed adipose and gland tissue at uniform literature-derived density) to detailed schemes (segmented adipose and gland with CT-derived densities). For detailed schemes, alternate mass density segmentation thresholds between adipose and gland are considered. Several literature-derived elemental compositions for adipose, gland and skin are compared. MC models derived from uncorrected CT images can yield large errors in dose calculations especially when used with detailed TAS. Differences in MAR method result in large differences in local doses when variations in CT number cause differences in tissue assignment. Between different MAR models (same TAS), PTV [Formula: see text] and skin [Formula: see text] each vary by up to 6%. Basic TAS (mixed adipose/gland tissue) generally yield higher dose metrics than detailed segmented schemes: PTV [Formula: see text] and skin [Formula: see text] are higher by up to 13% and 9% respectively. Employing alternate adipose, gland and skin elemental compositions can cause variations in PTV [Formula: see text] of up to 11% and skin [Formula: see text] of up to 30%. Overall, AAPM TG-43 overestimates dose to the PTV ([Formula: see text] on average 10% and up to 27%) and underestimates dose to the skin ([Formula: see text] on average 29% and up to 48%) compared to the various MC models derived using the post-MAR CT images

  4. Permanent-Magnet Meissner Bearing

    NASA Technical Reports Server (NTRS)

    Robertson, Glen A.

    1994-01-01

    Permanent-magnet meissner bearing features inherently stable, self-centering conical configuration. Bearing made stiffer or less stiff by selection of magnets, springs, and spring adjustments. Cylindrical permanent magnets with axial magnetization stacked coaxially on rotor with alternating polarity. Typically, rare-earth magnets used. Magnets machined and fitted together to form conical outer surface.

  5. Neurocognitive function and quality of life in patients with newly diagnosed brain metastasis after treatment with intra-operative cesium-131 brachytherapy: a prospective trial.

    PubMed

    Pham, Anthony; Yondorf, Menachem Z; Parashar, Bhupesh; Scheff, Ronald J; Pannullo, Susan C; Ramakrishna, Rohan; Stieg, Philip E; Schwartz, Theodore H; Wernicke, A Gabriella

    2016-03-01

    Intraoperative permanent Cesium-131 (Cs-131) brachytherapy can provide a viable alternative to WBRT with excellent response rates and minimal toxicity. This study reports the results of the prospective trial of the impact of intraoperative Cs-131 on neurocognitive function and quality of life (QoL) in patients with resected brain metastases. Between 2010 and 2012, 24 patients with newly diagnosed metastasis to the brain were accrued on a prospective protocol and treated with Cs-131 brachytherapy seeds after surgical resection. Physicians administered the mini-mental status examination (MMSE) and functional assessment of cancer therapy-brain (FACT-Br) questionnaire to all patients before treatment and again every 2 months for the duration of 6 months with additional follow-up again at 12 months. Wilcoxon rank sum test was used to analyze statistically significant changes in MMSE over time and paired t test was used to analyze changes in FACT-BR. There was a statistical improvement in overall FACT-BR score at 4 and 6 months of follow-up when compared to baseline (162 vs. 143, P = 0.004; 164 vs. 143, P = 0.005 respectively) with a non-significant trend toward improvement at 2 and 12 months (154 vs. 143, P = 0.067; 159 vs. 149, P = 0.4). MMSE score was statistically improved at 4 and up to 12 months compared to pre-treatment MMSE (30 vs. 29, P = 0.017; 30 vs. 29, P = 0.001 respectively). Patients with brain metastasis who received intra-operative permanent Cs-131 brachytherapy implants saw an improvement of their neurocognitive status and self-assessment of QoL. In addition to the excellent local control of metastasis, this approach may contribute to the improvements in cognitive function and QOL.

  6. SU-E-T-546: Use of Implant Volume for Quality Assurance of Low Dose Rate Brachytherapy Treatment Plans

    SciTech Connect

    Wilkinson, D; Kolar, M

    2014-06-01

    Purpose: To analyze the application of volume implant (V100) data as a method for a global check of low dose rate (LDR) brachytherapy plans. Methods: Treatment plans for 335 consecutive patients undergoing permanent seed implants for prostate cancer and for 113 patients treated with plaque therapy for ocular melanoma were analyzed. Plaques used were 54 COMS (10 to 20 mm, notched and regular) and 59 Eye Physics EP917s with variable loading. Plots of treatment time x implanted activity per unit dose versus v100 ^.667 were made. V100 values were obtained using dose volume histograms calculated by the treatment planning systems (Variseed 8.02 and Plaque Simulator 5.4). Four different physicists were involved in planning the prostate seed cases; two physicists for the eye plaques. Results: Since the time and dose for the prostate cases did not vary, a plot of implanted activity vs V100 ^.667 was made. A linear fit with no intercept had an r{sup 2} = 0.978; more than 94% of the actual activities fell within 5% of the activities calculated from the linear fit. The greatest deviations were in cases where the implant volumes were large (> 100 cc). Both COMS and EP917 plaque linear fits were good (r{sup 2} = .967 and .957); the largest deviations were seen for large volumes. Conclusions: The method outlined here is effective for checking planning consistency and quality assurance of two types of LDR brachytherapy treatment plans (temporary and permanent). A spreadsheet for the calculations enables a quick check of the plan in situations were time is short (e.g. OR-based prostate planning)

  7. Modeling the impact of prostate edema on LDR brachytherapy: a Monte Carlo dosimetry study based on a 3D biphasic finite element biomechanical model

    NASA Astrophysics Data System (ADS)

    Mountris, K. A.; Bert, J.; Noailly, J.; Rodriguez Aguilera, A.; Valeri, A.; Pradier, O.; Schick, U.; Promayon, E.; Gonzalez Ballester, M. A.; Troccaz, J.; Visvikis, D.

    2017-03-01

    Prostate volume changes due to edema occurrence during transperineal permanent brachytherapy should be taken under consideration to ensure optimal dose delivery. Available edema models, based on prostate volume observations, face several limitations. Therefore, patient-specific models need to be developed to accurately account for the impact of edema. In this study we present a biomechanical model developed to reproduce edema resolution patterns documented in the literature. Using the biphasic mixture theory and finite element analysis, the proposed model takes into consideration the mechanical properties of the pubic area tissues in the evolution of prostate edema. The model’s computed deformations are incorporated in a Monte Carlo simulation to investigate their effect on post-operative dosimetry. The comparison of Day1 and Day30 dosimetry results demonstrates the capability of the proposed model for patient-specific dosimetry improvements, considering the edema dynamics. The proposed model shows excellent ability to reproduce previously described edema resolution patterns and was validated based on previous findings. According to our results, for a prostate volume increase of 10–20% the Day30 urethra D10 dose metric is higher by 4.2%–10.5% compared to the Day1 value. The introduction of the edema dynamics in Day30 dosimetry shows a significant global dose overestimation identified on the conventional static Day30 dosimetry. In conclusion, the proposed edema biomechanical model can improve the treatment planning of transperineal permanent brachytherapy accounting for post-implant dose alterations during the planning procedure.

  8. Introduction of Transperineal Image-Guided Prostate Brachytherapy

    SciTech Connect

    Aronowitz, Jesse N.

    2014-07-15

    The modern prostate brachytherapy procedure is characterized by ultrasound guidance, template assistance, and a return to a “closed” transperineal approach. This review traces the introduction and evolution of these elements and charts the development of the procedure from the ashes of previous, failed efforts.

  9. 10 CFR 35.2406 - Records of brachytherapy source accountability.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 1 2014-01-01 2014-01-01 false Records of brachytherapy source accountability. 35.2406 Section 35.2406 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Records § 35.2406... from storage, the name of the individual who removed them from storage, and the location of use; and...

  10. Brachytherapy treatment planning algorithm applied to prostate cancer

    NASA Astrophysics Data System (ADS)

    Herrera-Rodríguez, M. R.; Martínez-Dávalos, A.

    2000-10-01

    An application of Genetic Algorithms (GAs) for treatment planning optimization in prostate brachytherapy is presented. The importance of multi-objective selection criteria based on the contour of the volume of interest and radiosensitive structures such as the rectum and urethra is discussed. First results are obtained for a simple test case which presents radial symmetry.

  11. 21 CFR 892.5730 - Radionuclide brachytherapy source.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Radionuclide brachytherapy source. 892.5730 Section 892.5730 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Therapeutic Devices § 892.5730 Radionuclide...

  12. 21 CFR 892.5730 - Radionuclide brachytherapy source.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Radionuclide brachytherapy source. 892.5730 Section 892.5730 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Therapeutic Devices § 892.5730 Radionuclide...

  13. 21 CFR 892.5730 - Radionuclide brachytherapy source.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Radionuclide brachytherapy source. 892.5730 Section 892.5730 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Therapeutic Devices § 892.5730 Radionuclide...

  14. 21 CFR 892.5730 - Radionuclide brachytherapy source.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Radionuclide brachytherapy source. 892.5730 Section 892.5730 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Therapeutic Devices § 892.5730 Radionuclide...

  15. 21 CFR 892.5730 - Radionuclide brachytherapy source.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Radionuclide brachytherapy source. 892.5730 Section 892.5730 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Therapeutic Devices § 892.5730 Radionuclide...

  16. Photoacoustic imaging of prostate brachytherapy seeds with transurethral light delivery

    NASA Astrophysics Data System (ADS)

    Lediju Bell, Muyinatu A.; Guo, Xiaoyu; Song, Danny Y.; Boctor, Emad M.

    2014-03-01

    We present a novel approach to photoacoustic imaging of prostate brachytherapy seeds utilizing an existing urinary catheter for transurethral light delivery. Two canine prostates were surgically implanted with brachyther- apy seeds under transrectal ultrasound guidance. One prostate was excised shortly after euthanasia and fixed in gelatin. The second prostate was imaged in the native tissue environment shortly after euthanasia. A urinary catheter was inserted in the urethra of each prostate. A 1-mm core diameter optical fiber coupled to a 1064 nm Nd:YAG laser was inserted into the urinary catheter. Light from the fiber was either directed mostly parallel to the fiber axis (i.e. end-fire fire) or mostly 90° to the fiber axis (i.e. side-fire fiber). An Ultrasonix SonixTouch scanner, transrectal ultrasound probe with curvilinear (BPC8-4) and linear (BPL9-5) arrays, and DAQ unit were utilized for synchronized laser light emission and photoacoustic signal acquisition. The implanted brachytherapy seeds were visualized at radial distances of 6-16 mm from the catheter. Multiple brachytherapy seeds were si- multaneously visualized with each array of the transrectal probe using both delay-and-sum (DAS) and short-lag spatial coherence (SLSC) beamforming. This work is the first to demonstrate the feasibility of photoacoustic imaging of prostate brachytherapy seeds using a transurethral light delivery method.

  17. Gadolinium neutron capture brachytherapy (GdNCB), a new treatment method for intravascular brachytherapy

    SciTech Connect

    Enger, Shirin A.; Rezaei, Arash; Munck af Rosenschoeld, Per; Lundqvist, Hans

    2006-01-15

    Restenosis is a major problem after balloon angioplasty and stent implantation. The aim of this study is to introduce gadolinium neutron capture brachytherapy (GdNCB) as a suitable modality for treatment of stenosis. The utility of GdNCB in intravascular brachytherapy (IVBT) of stent stenosis is investigated by using the GEANT4 and MCNP4B Monte Carlo radiation transport codes. To study capture rate, Kerma, absorbed dose and absorbed dose rate around a Gd-containing stent activated with neutrons, a 30 mm long, 5 mm diameter gadolinium foil is chosen. The input data is a neutron spectrum used for clinical neutron capture therapy in Studsvik, Sweden. Thermal neutron capture in gadolinium yields a spectrum of high-energy gamma photons, which due to the build-up effect gives an almost flat dose delivery pattern to the first 4 mm around the stent. The absorbed dose rate is 1.33 Gy/min, 0.25 mm from the stent surface while the dose to normal tissue is in order of 0.22 Gy/min, i.e., a factor of 6 lower. To spare normal tissue further fractionation of the dose is also possible. The capture rate is relatively high at both ends of the foil. The dose distribution from gamma and charge particle radiation at the edges and inside the stent contributes to a nonuniform dose distribution. This will lead to higher doses to the surrounding tissue and may prevent stent edge and in-stent restenosis. The position of the stent can be verified and corrected by the treatment plan prior to activation. Activation of the stent by an external neutron field can be performed days after catherization when the target cells start to proliferate and can be expected to be more radiation sensitive. Another advantage of the nonradioactive gadolinium stent is the possibility to avoid radiation hazard to personnel.

  18. Periodic permanent magnet focused klystron

    DOEpatents

    Ferguson, Patrick; Read, Michael; Ives, R Lawrence

    2015-04-21

    A periodic permanent magnet (PPM) klystron has beam transport structures and RF cavity structures, each of which has permanent magnets placed substantially equidistant from a beam tunnel formed about the central axis, and which are also outside the extent of a cooling chamber. The RF cavity sections also have permanent magnets which are placed substantially equidistant from the beam tunnel, but which include an RF cavity coupling to the beam tunnel for enhancement of RF carried by an electron beam in the beam tunnel.

  19. Calculated and measured brachytherapy dosimetry parameters in water for the Xoft Axxent X-Ray Source: an electronic brachytherapy source.

    PubMed

    Rivard, Mark J; Davis, Stephen D; DeWerd, Larry A; Rusch, Thomas W; Axelrod, Steve

    2006-11-01

    A new x-ray source, the model S700 Axxent X-Ray Source (Source), has been developed by Xoft Inc. for electronic brachytherapy. Unlike brachytherapy sources containing radionuclides, this Source may be turned on and off at will and may be operated at variable currents and voltages to change the dose rate and penetration properties. The in-water dosimetry parameters for this electronic brachytherapy source have been determined from measurements and calculations at 40, 45, and 50 kV settings. Monte Carlo simulations of radiation transport utilized the MCNP5 code and the EPDL97-based mcplib04 cross-section library. Inter-tube consistency was assessed for 20 different Sources, measured with a PTW 34013 ionization chamber. As the Source is intended to be used for a maximum of ten treatment fractions, tube stability was also assessed. Photon spectra were measured using a high-purity germanium (HPGe) detector, and calculated using MCNP. Parameters used in the two-dimensional (2D) brachytherapy dosimetry formalism were determined. While the Source was characterized as a point due to the small anode size, < 1 mm, use of the one-dimensional (1D) brachytherapy dosimetry formalism is not recommended due to polar anisotropy. Consequently, 1D brachytherapy dosimetry parameters were not sought. Calculated point-source model radial dose functions at gP(5) were 0.20, 0.24, and 0.29 for the 40, 45, and 50 kV voltage settings, respectively. For 1

  20. Seed based registration for intraoperative brachytherapy dosimetry: a comparison of methods

    NASA Astrophysics Data System (ADS)

    Su, Yi; Davis, Brian J.; Herman, Michael G.; Robb, Richard A.

    2006-03-01

    Several approaches for registering a subset of imaged points to their true origins were analyzed and compared for seed based TRUS-fluoroscopy registration. The methods include the Downhill Simplex method (DS), the Powell's method (POW), the Iterative Closest Point (ICP) method, the Robust Point Matching method (RPM) and variants of RPM. Several modifications were made to the standard RPM method to improve its performance. One hundred simulations were performed for each combination of noise level, seed detection rate and spurious points and the registration accuracy was evaluated and compared. The noise level ranges from 0 to 5mm, the seed detection ratio ranges from 0.2 to 0.6, and the number of spurious points ranges from 0 to 20. An actual clinical post-implant dataset from permanent prostate brachytherapy was used for the simulation study. The experiments provided evidence that our modified RPM method is superior to other methods, especially when there are many outliers. The RPM based method produced the best results at all noise levels and seed detection rates. The DS based method performed reasonably well, especially at low noise levels without spurious points. There was no significant performance difference between the standard RPM and our modified RPM methods without spurious points. The modified RPM methods outperformed the standard RPM method with large number of spurious points. The registration error was within 2mm, even with 20 outlier points and a noise level of 3mm.

  1. Repeat Brachytherapy for Patients With Residual or Recurrent Tumors of Oral Cavity

    SciTech Connect

    Yoshimura, Ryo-ichi; Shibuya, Hitoshi; Hayashi, Keiji; Nakagawa, Keiko; Toda, Kazuma; Watanabe, Hiroshi; Kaida, Atushi; Miura, Masahiko

    2012-07-15

    Purpose: To analyze data from patients receiving repeat brachytherapy (re-BT) for the treatment of residual or recurrent tumor in the oral cavity. Methods and Materials: Between January 2003 and December 2007, 62 patients who had undergone definitive BT as an initial treatment of oral cancer subsequently underwent re-BT for the treatment of residual or recurrent tumors at the diagnostic radiology and oncology department (Tokyo Medical and Dental University Hospital). Re-BT was performed 0.9-73 months (median, 5.7) after the initial BT. Au-198 grains were used as the re-BT source in all 62 patients, and an area of 0.8-6.3 cm{sup 2} (median, 3.1) was permanently irradiated with 60-110 Gy (median, 83) according to the system of Paterson-Parker. Results: The 2-year local control and overall survival rate was 53% and 66%, respectively, and local control significantly affected overall survival. Both local control and overall survival were affected by the initial tumor characteristics and the macroscopic appearance of the residual or recurrent tumor. Grade 3 or 4 complications were seen in 5 patients. The incidence of mandibular and mucosal complications was significantly related to a biologic effective dose of {alpha}/{beta} of 3 Gy to the surface of the gingiva and mucosa, respectively. Conclusion: Re-BT using Au-198 grains for the treatment of residual or recurrent tumor after definitive BT in the oral cavity is effective and well tolerated.

  2. Monte Carlo calculations and experimental measurements of dosimetric parameters of the IRA-103Pd brachytherapy source.

    PubMed

    Sadeghi, Mahdi; Raisali, Gholamreza; Hosseini, S Hamed; Shavar, Arzhang

    2008-04-01

    This article presents a brachytherapy source having 103Pd adsorbed onto a cylindrical silver rod that has been developed by the Agricultural, Medical, and Industrial Research School for permanent implant applications. Dosimetric characteristics (radial dose function, anisotropy function, and anisotropy factor) of this source were experimentally and theoretically determined in terms of the updated AAPM Task group 43 (TG-43U1) recommendations. Monte Carlo simulations were used to calculate the dose rate constant. Measurements were performed using TLD-GR200A circular chip dosimeters using standard methods employing thermoluminescent dosimeters in a Perspex phantom. Precision machined bores in the phantom located the dosimeters and the source in a reproducible fixed geometry, providing for transverse-axis and angular dose profiles over a range of distances from 0.5 to 5 cm. The Monte Carlo N-particle (MCNP) code, version 4C simulation techniques have been used to evaluate the dose-rate distributions around this model 103Pd source in water and Perspex phantoms. The Monte Carlo calculated dose rate constant of the IRA-103Pd source in water was found to be 0.678 cGy h(-1) U(-1) with an approximate uncertainty of +/-0.1%. The anisotropy function, F(r, theta), and the radial dose function, g(r), of the IRA- 103Pd source were also measured in a Perspex phantom and calculated in both Perspex and liquid water phantoms.

  3. Results of brachytherapy for cancer of the tongue with special emphasis on local prognosis

    SciTech Connect

    Horiuchi, J.; Okuyama, T.; Shibuya, H.; Takeda, M.

    1982-05-01

    One hundred and sixty-six patients with squamous cell carcinoma of the tongue were treated with radiation. Treatment modalities were mainly interstitial implant with or without external beam irradiation, except for early lesions, which were treated with intraoral electron beam therapy. Analysis was made on the local prognosis of the lesion to clarify the indications for interstitial therapy, especially the combined program with external beam therapy, and the time-dose relationship of the brachytherapy. Local recurrence-free rates (two years) were 94% in T1, 77% in T2 and 32% in T3 lesions, respectively. For T1 and surperficial or exophytic T2 lesions, the local recurrence-free rate was excellent with the interstitial therapy alone using either permanent implants of gold grain or radium implants. Therefore, prior external beam therapy seemed to be unnecessary for these lesions. When the treated area was less than 10 cm/sup 2/, subsequent complications were not likely even if the TDF (time-dose factor) value was high. Most of the patients who received combined external beam and interstitial therapy showed infiltrative T2 and a majority of the T3 lesions. In these patients, it was apparent that most of the total dose should be given from the interstitial implant after a small prior dose with external irradiation, because these lesions could not be cured even if the external dose was increased.

  4. Absolute calorimetric calibration of low energy brachytherapy sources

    NASA Astrophysics Data System (ADS)

    Stump, Kurt E.

    In the past decade there has been a dramatic increase in the use of permanent radioactive source implants in the treatment of prostate cancer. A small radioactive source encapsulated in a titanium shell is used in this type of treatment. The radioisotopes used are generally 125I or 103Pd. Both of these isotopes have relatively short half-lives, 59.4 days and 16.99 days, respectively, and have low-energy emissions and a low dose rate. These factors make these sources well suited for this application, but the calibration of these sources poses significant metrological challenges. The current standard calibration technique involves the measurement of ionization in air to determine the source air-kerma strength. While this has proved to be an improvement over previous techniques, the method has been shown to be metrologically impure and may not be the ideal means of calbrating these sources. Calorimetric methods have long been viewed to be the most fundamental means of determining source strength for a radiation source. This is because calorimetry provides a direct measurement of source energy. However, due to the low energy and low power of the sources described above, current calorimetric methods are inadequate. This thesis presents work oriented toward developing novel methods to provide direct and absolute measurements of source power for low-energy low dose rate brachytherapy sources. The method is the first use of an actively temperature-controlled radiation absorber using the electrical substitution method to determine total contained source power of these sources. The instrument described operates at cryogenic temperatures. The method employed provides a direct measurement of source power. The work presented here is focused upon building a metrological foundation upon which to establish power-based calibrations of clinical-strength sources. To that end instrument performance has been assessed for these source strengths. The intent is to establish the limits of

  5. Improved dosimetry techniques for intravascular brachytherapy

    NASA Astrophysics Data System (ADS)

    Sehgal, Varun

    Coronary artery disease leads to the accumulation of atheromatous plaque leading to coronary stenosis. Coronary intervention techniques such as balloon angioplasty and atherectomy are used to address coronary stenosis and establish a stable lumen thus enhancing blood flow to the myocardium. Restenosis or re-blockage of the arteries is a major limitation of the above mentioned interventional techniques. Neointimal hyperplasia or proliferation of cells in response to the vascular injury as a result of coronary intervention is considered to be one of the major causes of restenosis. Recent studies indicated that irradiation of the coronary lesion site, with radiation doses ranging from 15 to 30 Gy, leads to diminishing neointimal hyperplasia with subsequent reduction in restenosis. The radiation dose is given by catheter-based radiation delivery systems using beta-emitters 90Sr/90Y, 32P and gamma-emitting 192Ir among others. However the dose schema used for dose prescription for these sources are relatively simplistic, and are based on calculations using uniform homogenous water or tissue media and simple cylinder geometry. Stenotic coronary vessels are invariably lined with atheromatous plaque of heterogeneous composition, the radiation dose distribution obtained from such dosimetry data can cause significant variations in the actual dose received by a given patient. Such discrepancies in dose calculation can introduce relatively large uncertainties in the limits of dose window for effective and safe application of intravascular brachytherapy, and consequently in the clinical evaluation of the efficacy of this modality. In this research study we investigated the effect of different geometrical and material heterogeneities, including residual plaque, catheter non-centering, lesion eccentricity and cardiac motion on the radiation dose delivered at the lesion site. Correction factors including dose perturbation factors and dose variation factors have been calculated

  6. Perioperative high dose rate (HDR) brachytherapy in unresectable locally advanced pancreatic tumors

    PubMed Central

    Waniczek, Dariusz; Piecuch, Jerzy; Mikusek, Wojciech; Arendt, Jerzy; Białas, Brygida

    2011-01-01

    Purpose The aim of the study was to present an original technique of catheter implantation for perioperative HDR-Ir192 brachytherapy in patients after palliative operations of unresectable locally advanced pancreatic tumors and to estimate the influence of perioperative HDR-Ir192 brachytherapy on pain relief in terminal pancreatic cancer patients. Material and methods Eight patients with pancreatic tumors located in the head of pancreas underwent palliative operations with the use of HDR-Ir192 brachytherapy. All patients qualified for surgery reported pain of high intensity and had received narcotic painkillers prior to operation. During the last phase of the surgery, the Nucletron® catheters were implanted in patients to prepare them for later perioperative brachytherapy. Since the 6th day after surgery HDR brachytherapy was performed. Before each brachytherapy fraction the location of implants were checked using fluoroscopy. A fractional dose was 5 Gy and a total dose was 20 Gy in the area of radiation. A comparative study of two groups of patients (with and without brachytherapy) with stage III pancreatic cancer according to the TNM scale was taken in consideration. Results and Conclusions The authors claim that the modification of catheter implantation using specially designed cannula, facilitates the process of inserting the catheter into the tumor, shortens the time needed for the procedure, and reduces the risk of complications. Mean survival time was 5.7 months. In the group of performed brachytherapy, the mean survival time was 6.7 months, while in the group of no brachytherapy performed – 4.4 months. In the group of brachytherapy, only one patient increased the dose of painkillers in the last month of his life. Remaining patients took constant doses of medicines. Perioperative HDR-Ir192 brachytherapy could be considered as a practical application of adjuvant therapy for pain relief in patients with an advanced pancreatic cancer. PMID:27895674

  7. Trends in the Utilization of Brachytherapy in Cervical Cancer in the United States

    SciTech Connect

    Han, Kathy; Milosevic, Michael; Fyles, Anthony; Pintilie, Melania; Viswanathan, Akila N.

    2013-09-01

    Purpose: To determine the trends in brachytherapy use in cervical cancer in the United States and to identify factors and survival benefits associated with brachytherapy treatment. Methods and Materials: Using the Surveillance, Epidemiology, and End Results (SEER) database, we identified 7359 patients with stages IB2-IVA cervical cancer treated with external beam radiation therapy (EBRT) between 1988 and 2009. Propensity score matching was used to adjust for differences between patients who received brachytherapy and those who did not from 2000 onward (after the National Cancer Institute alert recommending concurrent chemotherapy). Results: Sixty-three percent of the 7359 women received brachytherapy in combination with EBRT, and 37% received EBRT alone. The brachytherapy utilization rate has decreased from 83% in 1988 to 58% in 2009 (P<.001), with a sharp decline of 23% in 2003 to 43%. Factors associated with higher odds of brachytherapy use include younger age, married (vs single) patients, earlier years of diagnosis, earlier stage and certain SEER regions. In the propensity score-matched cohort, brachytherapy treatment was associated with higher 4-year cause-specific survival (CSS; 64.3% vs 51.5%, P<.001) and overall survival (OS; 58.2% vs 46.2%, P<.001). Brachytherapy treatment was independently associated with better CSS (hazard ratio [HR], 0.64; 95% confidence interval [CI], 0.57-0.71), and OS (HR 0.66; 95% CI, 0.60 to 0.74). Conclusions: This population-based analysis reveals a concerning decline in brachytherapy utilization and significant geographic disparities in the delivery of brachytherapy in the United States. Brachytherapy use is independently associated with significantly higher CSS and OS and should be implemented in all feasible cases.

  8. MO-E-BRD-03: Intra-Operative Breast Brachytherapy: Is One Stop Shopping Best? [Non-invasive Image-Guided Breast Brachytherapy

    SciTech Connect

    Libby, B.

    2015-06-15

    Is Non-invasive Image-Guided Breast Brachytherapy Good? – Jess Hiatt, MS Non-invasive Image-Guided Breast Brachytherapy (NIBB) is an emerging therapy for breast boost treatments as well as Accelerated Partial Breast Irradiation (APBI) using HDR surface breast brachytherapy. NIBB allows for smaller treatment volumes while maintaining optimal target coverage. Considering the real-time image-guidance and immobilization provided by the NIBB modality, minimal margins around the target tissue are necessary. Accelerated Partial Breast Irradiation in brachytherapy: is shorter better? - Dorin Todor, PhD VCU A review of balloon and strut devices will be provided together with the origins of APBI: the interstitial multi-catheter implant. A dosimetric and radiobiological perspective will help point out the evolution in breast brachytherapy, both in terms of devices and the protocols/clinical trials under which these devices are used. Improvements in imaging, delivery modalities and convenience are among the factors driving the ultrashort fractionation schedules but our understanding of both local control and toxicities associated with various treatments is lagging. A comparison between various schedules, from a radiobiological perspective, will be given together with a critical analysis of the issues. to review and understand the evolution and development of APBI using brachytherapy methods to understand the basis and limitations of radio-biological ‘equivalence’ between fractionation schedules to review commonly used and proposed fractionation schedules Intra-operative breast brachytherapy: Is one stop shopping best?- Bruce Libby, PhD. University of Virginia A review of intraoperative breast brachytherapy will be presented, including the Targit-A and other trials that have used electronic brachytherapy. More modern approaches, in which the lumpectomy procedure is integrated into an APBI workflow, will also be discussed. Learning Objectives: To review past and current

  9. Cataract extraction after brachytherapy for malignant melanoma of the choroid

    SciTech Connect

    Fish, G.E.; Jost, B.F.; Snyder, W.I.; Fuller, D.G.; Birch, D.G. )

    1991-05-01

    Thirteen eyes of 55 consecutive patients treated with brachytherapy for malignant melanoma of the choroid developed postirradiation cataracts. Cataract development was more common in older patients and in patients with larger and more anterior tumors. Eleven eyes had extracapsular cataract extraction and intraocular lens implantation. Initial visual improvement occurred in 91% of eyes, with an average improvement of 5.5 lines. Visual acuity was maintained at 20/60 or better in 55% of the eyes over an average period of follow-up of 24 months (range, 6 to 40 months). These data suggest that, visually, cataract extraction can be helpful in selected patients who develop a cataract after brachytherapy for malignant melanoma of the choroid.

  10. Metal artefacts in MRI-guided brachytherapy of cervical cancer

    PubMed Central

    Owrangi, Amir; Ravi, Ananth; Song, William Y.

    2016-01-01

    The importance of assessing the metal-induced artefacts in magnetic resonance imaging (MRI)-guided brachytherapy is growing along with the increasing interest of integrating MRI into the treatment procedure of cervical cancer. Examples of metal objects in use include intracavitary cervical applicators and interstitial needles. The induced artefacts increase the uncertainties in the clinical workflow and can be a potential obstacle for the accurate delivery of the treatment. Overcoming this problem necessitates a good understanding of its originating sources. Several efforts are recorded in the literature to quantify the extent of such artefacts, in phantoms and in clinical practice. Here, we elaborate on the origin of metal-induced artefacts in the light of brachytherapy applications, while summarizing recent efforts that have been made to assess and overcome the induced distortions. PMID:27648092

  11. Review of advanced catheter technologies in radiation oncology brachytherapy procedures

    PubMed Central

    Zhou, Jun; Zamdborg, Leonid; Sebastian, Evelyn

    2015-01-01

    The development of new catheter and applicator technologies in recent years has significantly improved treatment accuracy, efficiency, and outcomes in brachytherapy. In this paper, we review these advances, focusing on the performance of catheter imaging and reconstruction techniques in brachytherapy procedures using magnetic resonance images and electromagnetic tracking. The accuracy of catheter reconstruction, imaging artifacts, and other notable properties of plastic and titanium applicators in gynecologic treatments are reviewed. The accuracy, noise performance, and limitations of electromagnetic tracking for catheter reconstruction are discussed. Several newly developed applicators for accelerated partial breast irradiation and gynecologic treatments are also reviewed. New hypofractionated high dose rate treatment schemes in prostate cancer and accelerated partial breast irradiation are presented. PMID:26203277

  12. Image-Guided Radiotherapy and -Brachytherapy for Cervical Cancer

    PubMed Central

    Dutta, Suresh; Nguyen, Nam Phong; Vock, Jacqueline; Kerr, Christine; Godinez, Juan; Bose, Satya; Jang, Siyoung; Chi, Alexander; Almeida, Fabio; Woods, William; Desai, Anand; David, Rick; Karlsson, Ulf Lennart; Altdorfer, Gabor

    2015-01-01

    Conventional radiotherapy for cervical cancer relies on clinical examination, 3-dimensional conformal radiotherapy (3D-CRT), and 2-dimensional intracavitary brachytherapy. Excellent local control and survival have been obtained for small early stage cervical cancer with definitive radiotherapy. For bulky and locally advanced disease, the addition of chemotherapy has improved the prognosis but toxicity remains significant. New imaging technology such as positron-emission tomography and magnetic resonance imaging has improved tumor delineation for radiotherapy planning. Image-guided radiotherapy (IGRT) may decrease treatment toxicity of whole pelvic radiation because of its potential for bone marrow, bowel, and bladder sparring. Tumor shrinkage during whole pelvic IGRT may optimize image-guided brachytherapy (IGBT), allowing for better local control and reduced toxicity for patients with cervical cancer. IGRT and IGBT should be integrated in future prospective studies for cervical cancer. PMID:25853092

  13. Image-guided radiotherapy and -brachytherapy for cervical cancer.

    PubMed

    Dutta, Suresh; Nguyen, Nam Phong; Vock, Jacqueline; Kerr, Christine; Godinez, Juan; Bose, Satya; Jang, Siyoung; Chi, Alexander; Almeida, Fabio; Woods, William; Desai, Anand; David, Rick; Karlsson, Ulf Lennart; Altdorfer, Gabor

    2015-01-01

    Conventional radiotherapy for cervical cancer relies on clinical examination, 3-dimensional conformal radiotherapy (3D-CRT), and 2-dimensional intracavitary brachytherapy. Excellent local control and survival have been obtained for small early stage cervical cancer with definitive radiotherapy. For bulky and locally advanced disease, the addition of chemotherapy has improved the prognosis but toxicity remains significant. New imaging technology such as positron-emission tomography and magnetic resonance imaging has improved tumor delineation for radiotherapy planning. Image-guided radiotherapy (IGRT) may decrease treatment toxicity of whole pelvic radiation because of its potential for bone marrow, bowel, and bladder sparring. Tumor shrinkage during whole pelvic IGRT may optimize image-guided brachytherapy (IGBT), allowing for better local control and reduced toxicity for patients with cervical cancer. IGRT and IGBT should be integrated in future prospective studies for cervical cancer.

  14. Review of advanced catheter technologies in radiation oncology brachytherapy procedures.

    PubMed

    Zhou, Jun; Zamdborg, Leonid; Sebastian, Evelyn

    2015-01-01

    The development of new catheter and applicator technologies in recent years has significantly improved treatment accuracy, efficiency, and outcomes in brachytherapy. In this paper, we review these advances, focusing on the performance of catheter imaging and reconstruction techniques in brachytherapy procedures using magnetic resonance images and electromagnetic tracking. The accuracy of catheter reconstruction, imaging artifacts, and other notable properties of plastic and titanium applicators in gynecologic treatments are reviewed. The accuracy, noise performance, and limitations of electromagnetic tracking for catheter reconstruction are discussed. Several newly developed applicators for accelerated partial breast irradiation and gynecologic treatments are also reviewed. New hypofractionated high dose rate treatment schemes in prostate cancer and accelerated partial breast irradiation are presented.

  15. Dosimetric characteristic of a new 125I brachytherapy source.

    PubMed

    Sadeghi, Mahdi; Khanmohammadi, Zahra

    2011-11-01

    A new brachytherapy (125)I source has been investigated at Iranian Agricultural, Medical and Industrial Research School. Dosimetric characteristics [dose-rate constant Λ, radial dose function g(l)(r) and anisotropy function F(r,)] of IRA-(125)I were theoretically determined in terms of the updated AAPM task group 43 (TG-43U1) recommendations. Versions 5 and 4C of the Monte Carlo radiation transport code were used to calculate the dosimetry parameters around the source. The Monte Carlo calculated dose-rate constant of the (125)I source in water was found to be 92×10(-4) Gy h(-1) U(-1) with an approximate uncertainty of ±3 %. Brachytherapy seed model, 6711-(125)I, carrying (125)I radionuclides, was modelled and benchmarked against previously published values. Finally, the calculated results were compared with the published results of those of other source manufacturers.

  16. Compound dual radiation action theory for 252Cf brachytherapy.

    PubMed

    Wang, C K; Zhang, X

    2004-01-01

    The existing dosimetry protocol that uses the concept of RBE for 252Cf brachytherapy contains large uncertainties. A new formula has been developed to correlate the biological effect (i.e. cell survival fraction) resulting from a mixed n + gamma radiation field with two physical quantities and two biological quantities. The formula is based on a pathway model evolved from that of the compound-dual-radiation-action (CDRA) theory, previously proposed by Rossi and Zaider. The new model employs the recently published data on radiation-induced DNA lesions. The new formula is capable of predicting quantitatively the synergistic effect caused by the interactions between neutron events and gamma ray events, and it is intended to be included into a new dosimetry protocol for future 252Cf brachytherapy.

  17. [Basic principles and results of brachytherapy in gynecological oncology].

    PubMed

    Kanaev, S V; Turkevich, V G; Baranov, S B; Savel'eva, V V

    2014-01-01

    The fundamental basics of contact radiation therapy (brachytherapy) for gynecological cancer are presented. During brachytherapy the principles of conformal radiotherapy should be implemented, the aim of which is to sum the maximum possible dose of radiation to the tumor and decrease the dose load in adjacent organs and tissues, which allows reducing the frequency of radiation damage at treatment of primary tumors. It is really feasible only on modern technological level, thanks to precision topometry preparation, optimal computer dosimetrical and radiobiological planning of each session and radiotherapy in general. Successful local and long-term results of the contact radiation therapy for cancer of cervix and endometrium are due to optimal anatomical and topometrical ratio of the tumor localization, radioactive sources, and also physical and radiobiological laws of distribution and effects of ionizing radiation, the dose load accounting rules.

  18. Detailed urethral dosimetry in the evaluation of prostate brachytherapy-related urinary morbidity

    SciTech Connect

    Allen, Zachariah A.; Merrick, Gregory S. . E-mail: gmerrick@wheelinghospital.com; Butler, Wayne M.; Wallner, Kent E.; Kurko, Brian; Anderson, Richard L.; Murray, Brian C.; Galbreath, Robert W.

    2005-07-15

    Purpose: To evaluate the relationship between urinary morbidity after prostate brachytherapy and urethral doses calculated at the base, midprostate, apex, and urogenital diaphragm. Methods and Materials: From February 1998 through July 2002, 186 consecutive patients without a prior history of a transurethral resection underwent monotherapeutic brachytherapy (no supplemental external beam radiation therapy or androgen deprivation therapy) with urethral-sparing techniques (average urethral dose 100%-140% minimum peripheral dose) for clinical T1c-T2b (2002 AJCC) prostate cancer. The median follow-up was 45.5 months. Urinary morbidity was defined by time to International Prostate Symptom Score (IPSS) resolution, maximum increase in IPSS, catheter dependency, and the need for postimplant surgical intervention. An alpha blocker was initiated approximately 2 weeks before implantation and continued at least until the IPSS returned to baseline. Evaluated parameters included overall urethral dose (average and maximum), doses to the base, midprostate, apex, and urogenital diaphragm, patient age, clinical T stage, preimplant IPSS, ultrasound volume, isotope, and D90 and V100/150/200. Results: Of the 186 patients, 176 (94.6%) had the urinary catheter permanently removed on the day of implantation with only 1 patient requiring a urinary catheter >5 days. No patient had a urethral stricture and only 2 patients (1.1%) required a postbrachytherapy transurethral resection of the prostate (TURP). For the entire cohort, IPSS on average peaked 2 weeks after implantation with a mean and median time to IPSS resolution of 14 and 3 weeks, respectively. For the entire cohort, only isotope predicted for IPSS resolution, while neither overall average prostatic urethra nor segmental urethral dose predicted for IPSS resolution. The maximum postimplant IPSS increase was best predicted by preimplant IPSS and the maximum apical urethral dose. Conclusions: With the routine use of prophylactic alpha

  19. Serum Testosterone Kinetics After Brachytherapy for Clinically Localized Prostate Cancer

    SciTech Connect

    Taira, Al V.; Merrick, Gregory S.; Galbreath, Robert W.; Butler, Wayne M.; Lief, Jonathan H.; Allen, Zachariah A.; Wallner, Kent E.

    2012-01-01

    Purpose: To evaluate temporal changes in testosterone after prostate brachytherapy and investigate the potential impact of these changes on response to treatment. Methods and Materials: Between January 2008 and March 2009, 221 consecutive patients underwent Pd-103 brachytherapy without androgen deprivation for clinically localized prostate cancer. Prebrachytherapy prostate-specific antigen (PSA) and serum testosterone were obtained for each patient. Repeat levels were obtained 3 months after brachytherapy and at least every 6 months thereafter. Multiple clinical, treatment, and dosimetric parameters were evaluated to determine an association with temporal testosterone changes. In addition, analysis was conducted to determine if there was an association between testosterone changes and treatment outcomes or the occurrence of a PSA spike. Results: There was no significant difference in serum testosterone over time after implant (p = 0.57). 29% of men experienced an increase {>=}25%, 23% of men experienced a decrease {>=}25%, and the remaining 48% of men had no notable change in testosterone over time. There was no difference in testosterone trends between men who received external beam radiotherapy and those who did not (p = 0.12). On multivariate analysis, preimplant testosterone was the only variable that consistently predicted for changes in testosterone over time. Men with higher than average testosterone tended to experience drop in testosterone (p < 0.001), whereas men with average or below average baseline testosterone had no significant change. There was no association between men who experienced PSA spike and testosterone temporal trends (p = 0.50) nor between initial PSA response and testosterone trends (p = 0.21). Conclusion: Prostate brachytherapy does not appear to impact serum testosterone over time. Changes in serum testosterone do not appear to be associated with PSA spike phenomena nor with initial PSA response to treatment; therefore, PSA response

  20. Primary calibration of coiled {sup 103}Pd brachytherapy sources

    SciTech Connect

    Paxton, Adam B.; Culberson, Wesley S.; DeWerd, Larry A.; Micka, John A.

    2008-01-15

    Coiled {sup 103}Pd brachytherapy sources have been developed by RadioMed Corporation for use as low-dose-rate (LDR) interstitial implants. The coiled sources are provided in integer lengths from 1 to 6 cm and address many common issues seen with traditional LDR brachytherapy sources. The current standard for determining the air-kerma strength (S{sub K}) of low-energy LDR brachytherapy sources is the National Institute of Standards and Technology's Wide-Angle Free-Air Chamber (NIST WAFAC). Due to geometric limitations, however, the NIST WAFAC is unable to determine the S{sub K} of sources longer than 1 cm. This project utilized the University of Wisconsin's Variable-Aperture Free-Air Chamber (UW VAFAC) to determine the S{sub K} of the longer coiled sources. The UW VAFAC has shown agreement in S{sub K} values of 1 cm length coils to within 1% of those determined with the NIST WAFAC, but the UW VAFAC does not share the same geometric limitations as the NIST WAFAC. A new source holder was constructed to hold the coiled sources in place during measurements with the UW VAFAC. Correction factors for the increased length of the sources have been determined and applied to the measurements. Using the new source holder and corrections, the S{sub K} of 3 and 6 cm coiled sources has been determined. Corrected UW VAFAC data and ionization current measurements from well chambers have been used to determine calibration coefficients for use in the measurement of 3 and 6 cm coiled sources in well chambers. Thus, the UW VAFAC has provided the first transferable, primary measurement of low-energy LDR brachytherapy sources with lengths greater than 1 cm.

  1. Cable attachment for a radioactive brachytherapy source capsule

    DOEpatents

    Gross, Ian G; Pierce, Larry A

    2006-07-18

    In cancer brachytherapy treatment, a small californium-252 neutron source capsule is attached to a guide cable using a modified crimping technique. The guide cable has a solid cylindrical end, and the attachment employs circumferential grooves micromachined in the solid cable end. The attachment was designed and tested, and hardware fabricated for use inside a radioactive hot cell. A welding step typically required in other cable attachments is avoided.

  2. Study of two different radioactive sources for prostate brachytherapy treatment

    SciTech Connect

    Pereira Neves, Lucio; Perini, Ana Paula; Souza Santos, William de; Caldas, Linda V.E.

    2015-07-01

    In this study we evaluated two radioactive sources for brachytherapy treatments. Our main goal was to quantify the absorbed doses on organs and tissues of an adult male patient, submitted to a brachytherapy treatment with two radioactive sources. We evaluated a {sup 192}Ir and a {sup 125}I radioactive sources. The {sup 192}Ir radioactive source is a cylinder with 0.09 cm in diameter and 0.415 cm long. The {sup 125}I radioactive source is also a cylinder, with 0.08 cm in diameter and 0.45 cm long. To evaluate the absorbed dose distribution on the prostate, and other organs and tissues of an adult man, a male virtual anthropomorphic phantom MASH, coupled in the radiation transport code MCNPX 2.7.0, was employed.We simulated 75, 90 and 102 radioactive sources of {sup 125}I and one of {sup 192}Ir, inside the prostate, as normally used in these treatments, and each treatment was simulated separately. As this phantom was developed in a supine position, the displacement of the internal organs of the chest, compression of the lungs and reduction of the sagittal diameter were all taken into account. For the {sup 192}Ir, the higher doses values were obtained for the prostate and surrounding organs, as the colon, gonads and bladder. Considering the {sup 125}I sources, with photons with lower energies, the doses to organs that are far from the prostate were lower. All values for the dose rates are in agreement with those recommended for brachytherapy treatments. Besides that, the new seeds evaluated in this work present usefulness as a new tool in prostate brachytherapy treatments, and the methodology employed in this work may be applied for other radiation sources, or treatments. (authors)

  3. Brachytherapy in Lip Carcinoma: Long-Term Results

    SciTech Connect

    Guibert, Mireille; David, Isabelle; Vergez, Sebastien; Rives, Michel; Filleron, Thomas; Bonnet, Jacques; Delannes, Martine

    2011-12-01

    Purpose: The aim of this study was to evaluate the effectiveness of low-dose-rate brachytherapy for local control and relapse-free survival in squamous cell and basal cell carcinomas of the lips. We compared two groups: one with tumors on the skin and the other with tumors on the lip. Patients and methods: All patients had been treated at Claudius Regaud Cancer Centre from 1990 to 2008 for squamous cell or basal cell carcinoma. Low-dose-rate brachytherapy was performed with iridium 192 wires according to the Paris system rules. On average, the dose delivered was 65 Gy. Results: 172 consecutive patients were included in our study; 69 had skin carcinoma (squamous cell or basal cell), and 92 had squamous cell mucosal carcinoma. The average follow-up time was 5.4 years. In the skin cancer group, there were five local recurrences and one lymph node recurrence. In the mucosal cancer group, there were ten local recurrences and five lymph node recurrences. The 8-year relapse-free survival for the entire population was 80%. The 8-year relapse-free survival was 85% for skin carcinoma 75% for mucosal carcinoma, with no significant difference between groups. The functional results were satisfactory for 99% of patients, and the cosmetic results were satisfactory for 92%. Maximal toxicity observed was Grade 2. Conclusions: Low-dose-rate brachytherapy can be used to treat lip carcinomas at Stages T1 and T2 as the only treatment with excellent results for local control and relapse-free survival. The benefits of brachytherapy are also cosmetic and functional, with 91% of patients having no side effects.

  4. Monte Carlo study of LDR seed dosimetry with an application in a clinical brachytherapy breast implant

    SciTech Connect

    Furstoss, C.; Reniers, B.; Bertrand, M. J.; Poon, E.; Carrier, J.-F.; Keller, B. M.; Pignol, J. P.; Beaulieu, L.; Verhaegen, F.

    2009-05-15

    A Monte Carlo (MC) study was carried out to evaluate the effects of the interseed attenuation and the tissue composition for two models of {sup 125}I low dose rate (LDR) brachytherapy seeds (Medi-Physics 6711, IBt InterSource) in a permanent breast implant. The effect of the tissue composition was investigated because the breast localization presents heterogeneities such as glandular and adipose tissue surrounded by air, lungs, and ribs. The absolute MC dose calculations were benchmarked by comparison to the absolute dose obtained from experimental results. Before modeling a clinical case of an implant in heterogeneous breast, the effects of the tissue composition and the interseed attenuation were studied in homogeneous phantoms. To investigate the tissue composition effect, the dose along the transverse axis of the two seed models were calculated and compared in different materials. For each seed model, three seeds sharing the same transverse axis were simulated to evaluate the interseed effect in water as a function of the distance from the seed. A clinical study of a permanent breast {sup 125}I implant for a single patient was carried out using four dose calculation techniques: (1) A TG-43 based calculation, (2) a full MC simulation with realistic tissues and seed models, (3) a MC simulation in water and modeled seeds, and (4) a MC simulation without modeling the seed geometry but with realistic tissues. In the latter, a phase space file corresponding to the particles emitted from the external surface of the seed is used at each seed location. The results were compared by calculating the relevant clinical metrics V{sub 85}, V{sub 100}, and V{sub 200} for this kind of treatment in the target. D{sub 90} and D{sub 50} were also determined to evaluate the differences in dose and compare the results to the studies published for permanent prostate seed implants in literature. The experimental results are in agreement with the MC absolute doses (within 5% for EBT

  5. Fabrication of cesium-137 brachytherapy sources using vitrification technology.

    PubMed

    Dash, Ashutosh; Varma, R N; Ram, Ramu; Saxena, S K; Mathakar, A R; Avhad, B G; Sastry, K V S; Sangurdekar, P R; Venkatesh, Meera

    2009-08-01

    137Cs source in solid matrix encapsulated in stainless-steel at MBq (mCi) levels are widely used as brachytherapy sources for the treatment of carcinoma of cervix uteri. This article describes the large-scale preparation of such sources. The process of fabrication includes vitrification of 137Cs-sodium borosilicate glass, its transformation into spheres of 5-6 mm diameter, casting of glass spheres into a cylinder of 1.5 mm (varphi) x 80 mm (l) in a platinum mould, cutting of the moulds into 5-mm-long pieces, silver coating on the sources, and finally, encapsulation in stainless steel capsules. Development of safety precautions used to trap 137Cs escaping during borosilicate glass preparation is also described. The leach rates of the radioactive sources prepared by the above technology were within permissible limits, and the sources could be used for encapsulation in stainless steel capsules and supplied for brachytherapy applications. This development was aimed at promoting the potential utility of 137Cs-brachytherapy sources in the country and reducing the user's reliance on imported sources. Since its development, more than 1000 such sources have been made by using 4.66 TBq(126 Ci) of 137Cs.

  6. Study of dose calculation on breast brachytherapy using prism TPS

    NASA Astrophysics Data System (ADS)

    Fendriani, Yoza; Haryanto, Freddy

    2015-09-01

    PRISM is one of non-commercial Treatment Planning System (TPS) and is developed at the University of Washington. In Indonesia, many cancer hospitals use expensive commercial TPS. This study aims to investigate Prism TPS which been applied to the dose distribution of brachytherapy by taking into account the effect of source position and inhomogeneities. The results will be applicable for clinical Treatment Planning System. Dose calculation has been implemented for water phantom and CT scan images of breast cancer using point source and line source. This study used point source and line source and divided into two cases. On the first case, Ir-192 seed source is located at the center of treatment volume. On the second case, the source position is gradually changed. The dose calculation of every case performed on a homogeneous and inhomogeneous phantom with dimension 20 × 20 × 20 cm3. The inhomogeneous phantom has inhomogeneities volume 2 × 2 × 2 cm3. The results of dose calculations using PRISM TPS were compared to literature data. From the calculation of PRISM TPS, dose rates show good agreement with Plato TPS and other study as published by Ramdhani. No deviations greater than ±4% for all case. Dose calculation in inhomogeneous and homogenous cases show similar result. This results indicate that Prism TPS is good in dose calculation of brachytherapy but not sensitive for inhomogeneities. Thus, the dose calculation parameters developed in this study were found to be applicable for clinical treatment planning of brachytherapy.

  7. Accelerated partial breast irradiation utilizing brachytherapy: patient selection and workflow

    PubMed Central

    Wobb, Jessica; Manyam, Bindu; Khan, Atif; Vicini, Frank

    2016-01-01

    Accelerated partial breast irradiation (APBI) represents an evolving technique that is a standard of care option in appropriately selected woman following breast conserving surgery. While multiple techniques now exist to deliver APBI, interstitial brachytherapy represents the technique used in several randomized trials (National Institute of Oncology, GEC-ESTRO). More recently, many centers have adopted applicator-based brachytherapy to deliver APBI due to the technical complexities of interstitial brachytherapy. The purpose of this article is to review methods to evaluate and select patients for APBI, as well as to define potential workflow mechanisms that allow for the safe and effective delivery of APBI. Multiple consensus statements have been developed to guide clinicians on determining appropriate candidates for APBI. However, recent studies have demonstrated that these guidelines fail to stratify patients according to the risk of local recurrence, and updated guidelines are expected in the years to come. Critical elements of workflow to ensure safe and effective delivery of APBI include a multidisciplinary approach and evaluation, optimization of target coverage and adherence to normal tissue guideline constraints, and proper quality assurance methods. PMID:26985202

  8. [Brachytherapy in France: current situation and economic outlook due to the unavailability of iridium wires].

    PubMed

    Le Vu, B; Boucher, S

    2014-10-01

    In 2013, about 6000 patients were treated with brachytherapy, the number diminishing by 2.6% per year since 2008. Prostate, breast and gynecological cancers are the most common types of cancers. Since 2008, the number of brachytherapy facilities has decreased by 18%. In medicoeconomic terms, brachytherapy faces many problems: the coding system is outdated; brachytherapy treatments cost as much as internal radiation; fees do not cover costs; since iridium wire has disappeared from the market, the technique will be transferred to more expensive high-speed or pulse dose rates. The French financing grid based on the national study of costs lags behind changes in such treatments and in the best of cases, hospitals resorting to alternatives such as in-hospital brachytherapy are funded at 46% of their additional costs. Brachytherapy is a reference technique. With intense pressure on hospital pricing, financing brachytherapy facilities will become even more problematic as a consequence of the disappearance of iridium 192 wires. The case of brachytherapy illustrates the limits of the French financing system and raises serious doubts as to its responsiveness.

  9. Perspectives of brachytherapy: patterns of care, new technologies, and "new biology".

    PubMed

    Guedea, F

    2014-10-01

    Brachytherapy has come a long way from its beginnings nearly a century ago. In recent years, brachytherapy has become ever more sophisticated thanks to a multitude of technological developments, including high-dose rate afterloading machines, image-guidance, and advanced planning systems. One of the advantages of brachytherapy, apart from the well-known capability of delivering highly conformal doses directly to the target, is that it is highly adaptable and can be used as a primary, adjunct, or salvage treatment. However, despite the existence of international treatment guidelines, the clinical practice of brachytherapy varies greatly by region, country, and even institution. In the present article, we provide an overview of recent findings from the Patterns of Care for Brachytherapy in Europe (PCBE) Study and we discuss new technologies used in brachytherapy and the emerging concept of "new biology" that supports the use of high-dose brachytherapy. Compared to the 1990s, the use of brachytherapy has increased substantially and it is expected to continue growing in the future as it becomes ever more precise and efficient.

  10. A compilation of current regulations, standards and guidelines in remote afterloading brachytherapy

    SciTech Connect

    Tortorelli, J.P.; Simion, G.P.; Kozlowski, S.D.

    1994-10-01

    Over a dozen government and professional organizations in the United States and Europe have issued regulations and guidance concerning quality management in the practice of remote afterloading brachytherapy. Information from the publications of these organizations was collected and collated for this report. This report provides the brachytherapy licensee access to a broad field of quality management information in a single, topically organized document.

  11. 10 CFR 35.400 - Use of sources for manual brachytherapy.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... therapeutic medical uses: (a) As approved in the Sealed Source and Device Registry; or (b) In research in... 10 Energy 1 2012-01-01 2012-01-01 false Use of sources for manual brachytherapy. 35.400 Section 35.400 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy §...

  12. Lodestone: Nature's own permanent magnet

    NASA Technical Reports Server (NTRS)

    Wasilewski, P.

    1976-01-01

    Magnetic hysteresis and microstructural details are presented which explain why the class of magnetic iron ores defined as proto-lodestones, can behave as permanent magnets, i.e. lodestones. Certain of these proto-lodestones which are not permanent magnets can be made into permanent magnets by charging in a field greater than 1000 oersted. This fact, other experimental observations, and field evidence from antiquity and the middle ages, which seems to indicate that lodestones are found as localized patches within massive ore bodies, suggests that lightning might be responsible for the charging of lodestones. The large remanent magnetization, high values of coercive force, and good time stability for the remanent magnetization are all characteristics of proto-lodestone iron ores which behave magnetically as fine scale ( 10 micrometer) intergrowths when subjected to magnetic hysteresis analysis. The magnetic results are easily understood by analysis of the complex proto lodestone microstructural patterns observable at the micrometer scale and less.

  13. Novel treatment options for nonmelanoma skin cancer: focus on electronic brachytherapy

    PubMed Central

    Kasper, Michael E; Chaudhary, Ahmed A

    2015-01-01

    Nonmelanoma skin cancer (NMSC) is an increasing health care issue in the United States, significantly affecting quality of life and impacting health care costs. Radiotherapy has a long history in the treatment of NMSC. Shortly after the discovery of X-rays and 226Radium, physicians cured patients with NMSC using these new treatments. Both X-ray therapy and brachytherapy have evolved over the years, ultimately delivering higher cure rates and lower toxicity. Electronic brachytherapy for NMSC is based on the technical and clinical data obtained from radionuclide skin surface brachytherapy and the small skin surface applicators developed over the past 25 years. The purpose of this review is to introduce electronic brachytherapy in the context of the history, data, and utilization of traditional radiotherapy and brachytherapy. PMID:26648763

  14. Air kerma and absorbed dose standards for reference dosimetry in brachytherapy

    PubMed Central

    2014-01-01

    This article reviews recent developments in primary standards for the calibration of brachytherapy sources, with an emphasis on the currently most common photon-emitting radionuclides. The introduction discusses the need for reference dosimetry in brachytherapy in general. The following section focuses on the three main quantities, i.e. reference air kerma rate, air kerma strength and absorbed dose rate to water, which are currently used for the specification of brachytherapy photon sources and which can be realized with primary standards from first principles. An overview of different air kerma and absorbed dose standards, which have been independently developed by various national metrology institutes over the past two decades, is given in the next two sections. Other dosimetry techniques for brachytherapy will also be discussed. The review closes with an outlook on a possible transition from air kerma to absorbed dose to water-based calibrations for brachytherapy sources in the future. PMID:24814696

  15. SU-F-BRA-06: Dose Distributions for the CivaSheet Pd-103 Directional Brachytherapy Device

    SciTech Connect

    Rivard, MJ

    2015-06-15

    Purpose: A flexible polymer membrane (CivaSheet) has been developed by CivaTech Oncology, Inc. (Research Triangle Park, NC) for permanent brachytherapy. Distributed throughout the array are small plastic disks containing Pd-103 and gold foil shielding on one side to provide a directional dose distribution and facilitate imaging. This study evaluated dosimetry for the CivaSheet. Methods: Manufacturer-provided dimensional and compositional information for the device were compared to physical samples for validation of design information, then entered into the MCNP6 radiation transport code for dosimetry simulations. Three device sizes (6×6, 6×12, or 6×18 disk-arrays) were simulated as the membrane can be custom-sized preceding surgical placement. Dose to water was estimated with 0.01 cm resolution from the surface to 10 cm on both sides of the device. Because this is a novel device with calibration methods under development, results were normalized using DVHs to provide 90% prescription coverage to a plane positioned 0.5 cm from the front surfaces. This same normalization was used for creating isodose distributions. Results: Planar dose distributions of flat CivaSheets were relatively homogeneous with acceptable dose uniformity variations. Differences in the results between the differently sized CivaSheets were not significant. At 0.5 mm, 87% of the target volume was within the therapeutic dose range. Dose hotspots on the CivaSheet forward surfaces were directly above the disks. However, dose hotspots on the rear-facing surfaces were positioned between the disks. Doses in contact with the front surface were similar to those observed for currently available brachytherapy sources. Maximum doses that occurred on the rear surface were approximately 55 times lower than the dose on the front surface. Conclusion: Monte Carlo calculations validated the directional capabilities and advantageous dosimetry of the new Pd-103 brachytherapy device. It appears feasible to re

  16. Radiobiology for eye plaque brachytherapy and evaluation of implant duration and radionuclide choice using an objective function

    SciTech Connect

    Gagne, Nolan L.; Leonard, Kara L.; Rivard, Mark J.

    2012-06-15

    Purpose: Clinical optimization of Collaborative Ocular Melanoma Study (COMS) eye plaque brachytherapy is currently limited to tumor coverage, consensus prescription dosage, and dose calculations to ocular structures. The biologically effective dose (BED) of temporary brachytherapy treatments is a function of both chosen radionuclide R and implant duration T. This study endeavored to evaluate BED delivered to the tumor volume and surrounding ocular structures as a function of plaque position P, prescription dose, R, and T. Methods: Plaque-heterogeneity-corrected dose distributions were generated with MCNP5 for the range of currently available COMS plaques loaded with sources using three available low-energy radionuclides. These physical dose distributions were imported into the PINNACLE{sup 3} treatment planning system using the TG-43 hybrid technique and used to generate dose volume histograms for a T = 7 day implant within a reference eye geometry including the ciliary body, cornea, eyelid, foveola, lacrimal gland, lens, optic disc, optic nerve, retina, and tumor at eight standard treatment positions. The equation of Dale and Jones was employed to create biologically effective dose volume histograms (BEDVHs), allowing for BED volumetric analysis of all ROIs. Isobiologically effective prescription doses were calculated for T = 5 days down to 0.01 days, with BEDVHs subsequently generated for all ROIs using correspondingly reduced prescription doses. Objective functions were created to evaluate the BEDVHs as a function of R and T. These objective functions are mathematically accessible and sufficiently general to be applied to temporary or permanent brachytherapy implants for a variety of disease sites. Results: Reducing T from 7 to 0.01 days for a 10 mm plaque produced an average BED benefit of 26%, 20%, and 17% for {sup 103}Pd, {sup 125}I, and {sup 131}Cs, respectively, for all P; 16 and 22 mm plaque results were more position-dependent. {sup 103}Pd produced a 16

  17. Dosimetry Modeling for Focal Low-Dose-Rate Prostate Brachytherapy

    SciTech Connect

    Al-Qaisieh, Bashar; Mason, Josh; Bownes, Peter; Henry, Ann; Dickinson, Louise; Ahmed, Hashim U.; Emberton, Mark; Langley, Stephen

    2015-07-15

    Purpose: Focal brachytherapy targeted to an individual lesion(s) within the prostate may reduce side effects experienced with whole-gland brachytherapy. The outcomes of a consensus meeting on focal prostate brachytherapy were used to investigate optimal dosimetry of focal low-dose-rate (LDR) prostate brachytherapy targeted using multiparametric magnetic resonance imaging (mp-MRI) and transperineal template prostate mapping (TPM) biopsy, including the effects of random and systematic seed displacements and interseed attenuation (ISA). Methods and Materials: Nine patients were selected according to clinical characteristics and concordance of TPM and mp-MRI. Retrospectively, 3 treatment plans were analyzed for each case: whole-gland (WG), hemi-gland (hemi), and ultra-focal (UF) plans, with 145-Gy prescription dose and identical dose constraints for each plan. Plan robustness to seed displacement and ISA were assessed using Monte Carlo simulations. Results: WG plans used a mean 28 needles and 81 seeds, hemi plans used 17 needles and 56 seeds, and UF plans used 12 needles and 25 seeds. Mean D90 (minimum dose received by 90% of the target) and V100 (percentage of the target that receives 100% dose) values were 181.3 Gy and 99.8% for the prostate in WG plans, 195.7 Gy and 97.8% for the hemi-prostate in hemi plans, and 218.3 Gy and 99.8% for the focal target in UF plans. Mean urethra D10 was 205.9 Gy, 191.4 Gy, and 92.4 Gy in WG, hemi, and UF plans, respectively. Mean rectum D2 cm{sup 3} was 107.5 Gy, 77.0 Gy, and 42.7 Gy in WG, hemi, and UF plans, respectively. Focal plans were more sensitive to seed displacement errors: random shifts with a standard deviation of 4 mm reduced mean target D90 by 14.0%, 20.5%, and 32.0% for WG, hemi, and UF plans, respectively. ISA has a similar impact on dose-volume histogram parameters for all plan types. Conclusions: Treatment planning for focal LDR brachytherapy is feasible. Dose constraints are easily met with a notable

  18. WE-F-BRD-01: HDR Brachytherapy II: Integrating Imaging with HDR

    SciTech Connect

    Craciunescu, O; Todor, D; Leeuw, A de

    2014-06-15

    In recent years, with the advent of high/pulsed dose rate afterloading technology, advanced treatment planning systems, CT/MRI compatible applicators, and advanced imaging platforms, image-guided adaptive brachytherapy treatments (IGABT) have started to play an ever increasing role in modern radiation therapy. The most accurate way to approach IGABT treatment is to provide the infrastructure that combines in a single setting an appropriate imaging device, a treatment planning system, and a treatment unit. The Brachytherapy Suite is not a new concept, yet the modern suites are incorporating state-of-the-art imaging (MRI, CBCT equipped simulators, CT, and /or US) that require correct integration with each other and with the treatment planning and delivery systems. Arguably, an MRI-equipped Brachytherapy Suite is the ideal setup for real-time adaptive brachytherapy treatments. The main impediment to MRI-IGABT adoption is access to MRI scanners. Very few radiation oncology departments currently house MRI scanners, and even fewer in a dedicated Brachytherapy Suite. CBCT equipped simulators are increasingly offered by manufacturers as part of a Brachytherapy Suite installation. If optimized, images acquired can be used for treatment planning, or can be registered with other imaging modalities. This infrastructure is relevant for all forms of brachytherapy, especially those utilizing multi-fractionated courses of treatment such as prostate and cervix. Moreover, for prostate brachytherapy, US imaging systems can be part of the suite to allow for real-time HDR/LDR treatments. Learning Objectives: Understand the adaptive workflow of MR-based IGBT for cervical cancer. Familiarize with commissioning aspects of a CBCT equipped simulator with emphasis on brachytherapy applications Learn about the current status and future developments in US-based prostate brachytherapy.

  19. Variation in uterus position prior to brachytherapy of the cervix: A case report

    PubMed Central

    Georgescu, MT; Anghel, R

    2017-01-01

    Rationale: brachytherapy is administered in the treatment of patients with locally advanced cervical cancer following chemoradiotherapy. Lack of local anatomy evaluation prior to this procedure might lead to the selection of an inappropriate brachytherapy applicator, increasing the risk of side effects (e.g. uterus perforation, painful procedure ...). Objective: To assess the movement of the uterus and cervix prior to brachytherapy in patients with gynecological cancer, in order to select the proper type of brachytherapy applicator. Also we wanted to promote the replacement of the plain X-ray brachytherapy with the image-guided procedure. Methods and results: We presented the case of a 41-year-old female diagnosed with a biopsy that was proven cervical cancer stage IIIB. At diagnosis, the imaging studies identified an anteverted uterus. The patient underwent preoperative chemoradiotherapy. Prior to brachytherapy, the patient underwent a pelvic magnetic resonance imaging (MRI), which identified a displacement of the uterus in the retroverted position. Discussion: A great variety of brachytherapy applicators is available nowadays. Major changes in uterus position and lack of evaluation prior to brachytherapy might lead to a higher rate of incidents during this procedure. Also, by using orthogonal simulation and bidimensional (2D) treatment planning, brachytherapy would undoubtedly fail to treat the remaining tumoral tissue. This is the reason why we proposed the implementation of a prior imaging of the uterus and computed tomography (CT)/ MRI-based simulation in the brachytherapy procedure. Abbreviations: MRI = magnetic resonance imaging, CT = computed tomography, CTV = clinical target volume, DVH = dose-volume histogram, EBRT = external beam radiotherapy, GTV = gross tumor volume, Gy = Gray (unit), ICRU = International Commission of Radiation Units, IGRT = image guided radiotherapy, IM = internal margin, IMRT = image modulated radiotherapy, ITV = internal target

  20. Magnetic Fields: Visible and Permanent.

    ERIC Educational Resources Information Center

    Winkeljohn, Dorothy R.; Earl, Robert D.

    1983-01-01

    Children will be able to see the concept of a magnetic field translated into a visible reality using the simple method outlined. Standard shelf paper, magnets, iron filings, and paint in a spray can are used to prepare a permanent and well-detailed picture of the magnetic field. (Author/JN)

  1. Brachytherapy in cancer cervix: Time to move ahead from point A?

    PubMed Central

    Srivastava, Anurita; Datta, Niloy Ranjan

    2014-01-01

    Brachytherapy forms an integral part of the radiation therapy in cancer cervix. The dose prescription for intracavitary brachytherapy (ICBT) in cancer cervix is based on Tod and Meredith’s point A and has been in practice since 1938. This was proposed at a time when accessibility to imaging technology and dose computation facilities was limited. The concept has been in practice worldwide for more than half a century and has been the fulcrum of all ICBT treatments, strategies and outcome measures. The method is simple and can be adapted by all centres practicing ICBT in cancer cervix. However, with the widespread availability of imaging techniques, clinical use of different dose-rates, availability of a host of applicators fabricated with image compatible materials, radiobiological implications of dose equivalence and its impact on tumour and organs at risk; more and more weight is being laid down on individualised image based brachytherapy. Thus, computed tomography, magnetic-resonance imaging and even positron emission computerized tomography along with brachytherapy treatment planning system are being increasingly adopted with promising outcomes. The present article reviews the evolution of dose prescription concepts in ICBT in cancer cervix and brings forward the need for image based brachytherapy to evaluate clinical outcomes. As is evident, a gradual transition from “point” based brachytherapy to “profile” based image guided brachytherapy is gaining widespread acceptance for dose prescription, reporting and outcome evaluation in the clinical practice of ICBT in cancer cervix. PMID:25302176

  2. High-dose-rate brachytherapy in uterine cervical carcinoma

    SciTech Connect

    Patel, Firuza D. . E-mail: patelfd@glide.net.in; Rai, Bhavana; Mallick, Indranil; Sharma, Suresh C.

    2005-05-01

    Purpose: High-dose-rate (HDR) brachytherapy is in wide use for curative treatment of cervical cancer. The American Brachytherapy Society has recommended that the individual fraction size be <7.5 Gy and the range of fractions should be four to eight; however, many fractionation schedules, varying from institution to institution, are in use. We use 9 Gy/fraction of HDR in two to five fractions in patients with carcinoma of the uterine cervix. We found that our results and toxicity were comparable to those reported in the literature and hereby present our experience with this fractionation schedule. Methods and Materials: A total of 121 patients with Stage I-III carcinoma of the uterine cervix were treated with HDR brachytherapy between 1996 and 2000. The total number of patients analyzed was 113. The median patient age was 53 years, and the histopathologic type was squamous cell carcinoma in 93% of patients. The patients were subdivided into Groups 1 and 2. In Group 1, 18 patients with Stage Ib-IIb disease, tumor size <4 cm, and preserved cervical anatomy underwent simultaneous external beam radiotherapy to the pelvis to a dose of 40 Gy in 20 fractions within 4 weeks with central shielding and HDR brachytherapy of 9 Gy/fraction, given weekly, and interdigitated with external beam radiotherapy. The 95 patients in Group 2, who had Stage IIb-IIIb disease underwent external beam radiotherapy to the pelvis to a dose of 46 Gy in 23 fractions within 4.5 weeks followed by two sessions of HDR intracavitary brachytherapy of 9 Gy each given 1 week apart. The follow-up range was 3-7 years (median, 36.4 months). Late toxicity was graded according to the Radiation Therapy Oncology Group criteria. Results: The 5-year actuarial local control and disease-free survival rate was 74.5% and 62.0%, respectively. The actuarial local control rate at 5 years was 100% for Stage I, 80% for Stage II, and 67.2% for Stage III patients. The 5-year actuarial disease-free survival rate was 88.8% for

  3. High brachytherapy doses can counteract hypoxia in cervical cancer—a modelling study

    NASA Astrophysics Data System (ADS)

    Lindblom, Emely; Dasu, Alexandru; Beskow, Catharina; Toma-Dasu, Iuliana

    2017-01-01

    Tumour hypoxia is a well-known adverse factor for the outcome of radiotherapy. For cervical tumours in particular, several studies indicate large variability in tumour oxygenation. However, clinical evidence shows that the management of cervical cancer including brachytherapy leads to high rate of success. It was the purpose of this study to investigate whether the success of brachytherapy for cervical cancer, seemingly regardless of oxygenation status, could be explained by the characteristics of the brachytherapy dose distributions. To this end, a previously used in silico model of tumour oxygenation and radiation response was further developed to simulate the treatment of cervical cancer employing a combination of external beam radiotherapy and intracavitary brachytherapy. Using a clinically-derived brachytherapy dose distribution and assuming a homogeneous dose delivered by external radiotherapy, cell survival was assessed on voxel level by taking into account the variation of sensitivity with oxygenation as well as the effects of repair, repopulation and reoxygenation during treatment. Various scenarios were considered for the conformity of the brachytherapy dose distribution to the hypoxic region in the target. By using the clinically-prescribed brachytherapy dose distribution and varying the total dose delivered with external beam radiotherapy in 25 fractions, the resulting values of the dose for 50% tumour control, D 50, were in agreement with clinically-observed values for high cure rates if fast reoxygenation was assumed. The D 50 was furthermore similar for the different degrees of conformity of the brachytherapy dose distribution to the tumour, regardless of whether the hypoxic fraction was 10%, 25%, or 40%. To achieve 50% control with external RT only, a total dose of more than 70 Gy in 25 fractions would be required for all cases considered. It can thus be concluded that the high doses delivered in brachytherapy can counteract the increased

  4. MO-E-BRD-01: Is Non-Invasive Image-Guided Breast Brachytherapy Good?

    SciTech Connect

    Hiatt, J.

    2015-06-15

    Is Non-invasive Image-Guided Breast Brachytherapy Good? – Jess Hiatt, MS Non-invasive Image-Guided Breast Brachytherapy (NIBB) is an emerging therapy for breast boost treatments as well as Accelerated Partial Breast Irradiation (APBI) using HDR surface breast brachytherapy. NIBB allows for smaller treatment volumes while maintaining optimal target coverage. Considering the real-time image-guidance and immobilization provided by the NIBB modality, minimal margins around the target tissue are necessary. Accelerated Partial Breast Irradiation in brachytherapy: is shorter better? - Dorin Todor, PhD VCU A review of balloon and strut devices will be provided together with the origins of APBI: the interstitial multi-catheter implant. A dosimetric and radiobiological perspective will help point out the evolution in breast brachytherapy, both in terms of devices and the protocols/clinical trials under which these devices are used. Improvements in imaging, delivery modalities and convenience are among the factors driving the ultrashort fractionation schedules but our understanding of both local control and toxicities associated with various treatments is lagging. A comparison between various schedules, from a radiobiological perspective, will be given together with a critical analysis of the issues. to review and understand the evolution and development of APBI using brachytherapy methods to understand the basis and limitations of radio-biological ‘equivalence’ between fractionation schedules to review commonly used and proposed fractionation schedules Intra-operative breast brachytherapy: Is one stop shopping best?- Bruce Libby, PhD. University of Virginia A review of intraoperative breast brachytherapy will be presented, including the Targit-A and other trials that have used electronic brachytherapy. More modern approaches, in which the lumpectomy procedure is integrated into an APBI workflow, will also be discussed. Learning Objectives: To review past and current

  5. MO-E-BRD-00: Breast Brachytherapy: The Phoenix of Radiation Therapy

    SciTech Connect

    2015-06-15

    Is Non-invasive Image-Guided Breast Brachytherapy Good? – Jess Hiatt, MS Non-invasive Image-Guided Breast Brachytherapy (NIBB) is an emerging therapy for breast boost treatments as well as Accelerated Partial Breast Irradiation (APBI) using HDR surface breast brachytherapy. NIBB allows for smaller treatment volumes while maintaining optimal target coverage. Considering the real-time image-guidance and immobilization provided by the NIBB modality, minimal margins around the target tissue are necessary. Accelerated Partial Breast Irradiation in brachytherapy: is shorter better? - Dorin Todor, PhD VCU A review of balloon and strut devices will be provided together with the origins of APBI: the interstitial multi-catheter implant. A dosimetric and radiobiological perspective will help point out the evolution in breast brachytherapy, both in terms of devices and the protocols/clinical trials under which these devices are used. Improvements in imaging, delivery modalities and convenience are among the factors driving the ultrashort fractionation schedules but our understanding of both local control and toxicities associated with various treatments is lagging. A comparison between various schedules, from a radiobiological perspective, will be given together with a critical analysis of the issues. to review and understand the evolution and development of APBI using brachytherapy methods to understand the basis and limitations of radio-biological ‘equivalence’ between fractionation schedules to review commonly used and proposed fractionation schedules Intra-operative breast brachytherapy: Is one stop shopping best?- Bruce Libby, PhD. University of Virginia A review of intraoperative breast brachytherapy will be presented, including the Targit-A and other trials that have used electronic brachytherapy. More modern approaches, in which the lumpectomy procedure is integrated into an APBI workflow, will also be discussed. Learning Objectives: To review past and current

  6. MO-E-BRD-02: Accelerated Partial Breast Irradiation in Brachytherapy: Is Shorter Better?

    SciTech Connect

    Todor, D.

    2015-06-15

    Is Non-invasive Image-Guided Breast Brachytherapy Good? – Jess Hiatt, MS Non-invasive Image-Guided Breast Brachytherapy (NIBB) is an emerging therapy for breast boost treatments as well as Accelerated Partial Breast Irradiation (APBI) using HDR surface breast brachytherapy. NIBB allows for smaller treatment volumes while maintaining optimal target coverage. Considering the real-time image-guidance and immobilization provided by the NIBB modality, minimal margins around the target tissue are necessary. Accelerated Partial Breast Irradiation in brachytherapy: is shorter better? - Dorin Todor, PhD VCU A review of balloon and strut devices will be provided together with the origins of APBI: the interstitial multi-catheter implant. A dosimetric and radiobiological perspective will help point out the evolution in breast brachytherapy, both in terms of devices and the protocols/clinical trials under which these devices are used. Improvements in imaging, delivery modalities and convenience are among the factors driving the ultrashort fractionation schedules but our understanding of both local control and toxicities associated with various treatments is lagging. A comparison between various schedules, from a radiobiological perspective, will be given together with a critical analysis of the issues. to review and understand the evolution and development of APBI using brachytherapy methods to understand the basis and limitations of radio-biological ‘equivalence’ between fractionation schedules to review commonly used and proposed fractionation schedules Intra-operative breast brachytherapy: Is one stop shopping best?- Bruce Libby, PhD. University of Virginia A review of intraoperative breast brachytherapy will be presented, including the Targit-A and other trials that have used electronic brachytherapy. More modern approaches, in which the lumpectomy procedure is integrated into an APBI workflow, will also be discussed. Learning Objectives: To review past and current

  7. Tattoos and Permanent Make-Up

    MedlinePlus

    ... For Consumers Consumer Information by Audience For Women Tattoos and Permanent Make-up Share Tweet Linkedin Pin ... Risks FDA's Role Tattoo Removal Options Types of Tattoos Permanent Tattoo : A needle inserts colored ink into ...

  8. Genetics Home Reference: permanent neonatal diabetes mellitus

    MedlinePlus

    ... Facebook Share on Twitter Your Guide to Understanding Genetic Conditions Search MENU Toggle navigation Home Page Search ... Conditions Genes Chromosomes & mtDNA Resources Help Me Understand Genetics Home Health Conditions permanent neonatal diabetes mellitus permanent ...

  9. Study of dose calculation on breast brachytherapy using prism TPS

    SciTech Connect

    Fendriani, Yoza; Haryanto, Freddy

    2015-09-30

    PRISM is one of non-commercial Treatment Planning System (TPS) and is developed at the University of Washington. In Indonesia, many cancer hospitals use expensive commercial TPS. This study aims to investigate Prism TPS which been applied to the dose distribution of brachytherapy by taking into account the effect of source position and inhomogeneities. The results will be applicable for clinical Treatment Planning System. Dose calculation has been implemented for water phantom and CT scan images of breast cancer using point source and line source. This study used point source and line source and divided into two cases. On the first case, Ir-192 seed source is located at the center of treatment volume. On the second case, the source position is gradually changed. The dose calculation of every case performed on a homogeneous and inhomogeneous phantom with dimension 20 × 20 × 20 cm{sup 3}. The inhomogeneous phantom has inhomogeneities volume 2 × 2 × 2 cm{sup 3}. The results of dose calculations using PRISM TPS were compared to literature data. From the calculation of PRISM TPS, dose rates show good agreement with Plato TPS and other study as published by Ramdhani. No deviations greater than ±4% for all case. Dose calculation in inhomogeneous and homogenous cases show similar result. This results indicate that Prism TPS is good in dose calculation of brachytherapy but not sensitive for inhomogeneities. Thus, the dose calculation parameters developed in this study were found to be applicable for clinical treatment planning of brachytherapy.

  10. Conformal Brachytherapy Planning for Cervical Cancer Using Transabdominal Ultrasound

    SciTech Connect

    Van Dyk, Sylvia Narayan, Kailash; Fisher, Richard; Bernshaw, David

    2009-09-01

    Purpose: To determine if transabdominal ultrasound (US) can be used for conformal brachytherapy in cervical cancer patients. Materials and Methods: Seventy-one patients with locoregionally advanced cervix cancer treated with chemoradiation and brachytherapy were included in this study. The protocol consisted of US-assisted tandem insertion and conformal US-based planning. Orthogonal films for applicator reconstruction were also taken. A standard plan was modified to suit the US-based volume and treatment was delivered. The patient then underwent a magnetic resonance imaging (MRI) scan with the applicators in situ. Retrospectively, individual standard (STD), US, and MRI plans were extrapolated for five fractions and superimposed onto the two-dimensional sagittal MRI images for comparison. Doses to Point A, target volume, International Commission on Radiation Units and Measurements (ICRU) 38 bladder and rectal points, and individualized bowel points were calculated on original implant geometry on Plato for each planning method. Results: STD (high-dose-rate) plans reported higher doses to Point A, target volume, ICRU 38 bladder and rectal points, and individualized bowel point compared with US and MRI plans. There was a statistically significant difference between standard plans and image-based plans-STD vs. US, STD vs. MRI, and STD vs. Final-having consistent (p {<=} 0.001) respectively for target volume, Point A, ICRU 38 bladder, and bowel point. US plan assessed on two-dimensional MRI image was comparable for target volume (p = 0.11), rectal point (p = 0.8), and vaginal mucosa (p = 0.19). Local control was 90%. Late bowel morbidity (G3, G4) was <2%. Conclusions: Transabdominal ultrasound offers an accurate, quick, accessible, and cost-effective method of conformal brachytherapy planning.

  11. Prospective evaluation of quality of life after interstitial brachytherapy for localized prostate cancer

    SciTech Connect

    Caffo, Orazio . E-mail: orazio.caffo@apss.tn.it; Fellin, Gianni; Bolner, Andrea; Coccarelli, Franco; Divan, Claudio; Frisinghelli, Michela; Mussari, Salvatore; Ziglio, Franco; Malossini, Gianni; Tomio, Luigi; Galligioni, Enzo

    2006-09-01

    Purpose: Permanent interstitial brachytherapy (IB) has become an increasingly appealing therapeutic option for localized prostate cancer (LPC) among physicians and patients because it involves short hospitalization and treatment and its postulated low degree of toxicity may reduce its impact on the patients' quality of life (QoL). The aim of this prospective study was to assess the impact of IB on the QoL of patients with LPC. Methods and Materials: A validated self-completed questionnaire was administered to the patients before and after IB and then at yearly intervals. The items allowed the identification of seven subscales exploring physical well-being (PHY), physical autonomy (POW), psychological well-being (PSY), relational life (REL), urinary function (URI), rectal function (REC), and sexual function (SEX). Results: The assessment of the QoL of 147 patients treated between May 2000 and February 2005 revealed no relevant differences in the PHY scale scores 1 month after IB or later, and the same was true of the POW, PSY, and REL scales. Urinary function significantly worsened after IB and returned to pretreatment levels only after 3 years; the impact of the treatment on the URI scale was greater in the patients with good baseline urinary function than in those presenting more urinary symptoms before IB. Rectal and sexual functions were significantly worse only at the post-IB evaluation. Conclusions: The results of the present study confirm that the impact of IB on the patients' QoL is low despite its transient negative effects on some function, and extend existing knowledge concerning QoL after IB.

  12. Theoretical and experimental determination of dosimetric characteristics for ADVANTAGE Pd-103 brachytherapy source.

    PubMed

    Meigooni, Ali S; Dini, Sharifeh A; Awan, Shahid B; Dou, Kai; Koona, Rafiq A

    2006-08-01

    ADVANTAGE Pd-103 brachytherapy source has been recently introduced by IsoAid for prostate permanent implants. Dosimetric characteristics (Dose rate constant, radial dose function, 2D-, and 1D-anisotropy functions) of this source model have been determined using both theoretical and experimental methods, following the updated TG-43U1 protocol. Derivation of the dose rate constant was based on recent NIST WAFAC calibration performed in accordance with the 1999 Standards. Measurements were performed in Solid Water using LiF TLD chips and the theoretical calculations were performed in Solid Water and liquid water phantom materials using PTRAN Monte Carlo code. The results of the Monte Carlo simulation have shown a dose rate constant of 0.69 cGyh(-1) U(-1) in liquid water and 0.67 cGyh(-1) U(-1) in Solid Water medium. The measured dose rate constant in Solid Water was found to be 0.68+/-8% cGyh(-1) U(-1), which is in a good agreement (within +/-5%) to the Monte Carlo simulated data. The 2D- and 1D-anisotropy functions of the ADVANTAGE Pd-103 source were calculated for radial distances ranging from 0.5 to 5.0 cm. Radial dose function was determined for radial distances ranging from 0.2 to 8.0 cm using line source approximation. All these calculations are based on L(eff) equal to 3.61 cm, calculated following TG-43U1 recommendations. The tabulated data for 2D-anisotropy function, 1D-anisotropy function, dose rate constant and radial dose function have been produced for clinical application of this source model.

  13. Iridium-192 interstitial brachytherapy for equine periocular tumours: treatment results and prognostic factors in 115 horses.

    PubMed

    Théon, A P; Pascoe, J R

    1995-03-01

    One hundred and fifteen horses with periocular tumours were treated with iridium-192 interstitial brachytherapy. Tumours included squamous cell carcinomas (n = 52) and sarcoids (n = 63). All horses were scheduled to receive 60 Gy (minimal tumour dose) given at a low dose rate (0.034 +/- 0.010 Gy/h). The mean and median follow-up times to last contact or death were 24 and 16 months, respectively. Chronic radiation reactions included palpebral fibrosis (10.4%), cataract (7.8%), keratitis and corneal ulceration (6.9%). Cosmetic changes included permanent epilation (21.7%) and hair dyspigmentation (78.3%). The one year progression-free survival (PFS) rates for sarcoids and carcinomas were 86.6% and 81.8% and the 5 year PFS rates were 74.0% and 63.5%, respectively. The horse age and sex, histopathological type, anatomical subsite and classification (WHO T1-3) were included in the analysis of prognostic factors. The only significant prognostic factor that independently affected PFS time was the WHO T-classification (P = 0.009, relative risk = 0.85). When compared to horses with T1 lesions, horses with T2 and T3 lesions had 1.8-fold and 3.4-fold increased risks, respectively, for tumour recurrence (relative excess risk). The one year PFS rates for T1, T2 and T3 lesions were 95.2%, 89.5% and 66.2%, respectively. The 5 year PFS rates were 72.2%, 74.0% and 53.1%, respectively. The results of this study indicate that irradiation is an effective treatment option for horses with T1-2 lesions and should be part of a combined treatment modality for horses with T3 lesions.

  14. Conventional Versus Automated Implantation of Loose Seeds in Prostate Brachytherapy: Analysis of Dosimetric and Clinical Results

    SciTech Connect

    Genebes, Caroline; Filleron, Thomas; Graff, Pierre; Jonca, Frédéric; Huyghe, Eric; Thoulouzan, Matthieu; Soulie, Michel; Malavaud, Bernard; Aziza, Richard; Brun, Thomas; Delannes, Martine; Bachaud, Jean-Marc

    2013-11-15

    Purpose: To review the clinical outcome of I-125 permanent prostate brachytherapy (PPB) for low-risk and intermediate-risk prostate cancer and to compare 2 techniques of loose-seed implantation. Methods and Materials: 574 consecutive patients underwent I-125 PPB for low-risk and intermediate-risk prostate cancer between 2000 and 2008. Two successive techniques were used: conventional implantation from 2000 to 2004 and automated implantation (Nucletron, FIRST system) from 2004 to 2008. Dosimetric and biochemical recurrence-free (bNED) survival results were reported and compared for the 2 techniques. Univariate and multivariate analysis researched independent predictors for bNED survival. Results: 419 (73%) and 155 (27%) patients with low-risk and intermediate-risk disease, respectively, were treated (median follow-up time, 69.3 months). The 60-month bNED survival rates were 95.2% and 85.7%, respectively, for patients with low-risk and intermediate-risk disease (P=.04). In univariate analysis, patients treated with automated implantation had worse bNED survival rates than did those treated with conventional implantation (P<.0001). By day 30, patients treated with automated implantation showed lower values of dose delivered to 90% of prostate volume (D90) and volume of prostate receiving 100% of prescribed dose (V100). In multivariate analysis, implantation technique, Gleason score, and V100 on day 30 were independent predictors of recurrence-free status. Grade 3 urethritis and urinary incontinence were observed in 2.6% and 1.6% of the cohort, respectively, with no significant differences between the 2 techniques. No grade 3 proctitis was observed. Conclusion: Satisfactory 60-month bNED survival rates (93.1%) and acceptable toxicity (grade 3 urethritis <3%) were achieved by loose-seed implantation. Automated implantation was associated with worse dosimetric and bNED survival outcomes.

  15. Matlab Tools: An Alternative to Planning Systems in Brachytherapy Treatments

    SciTech Connect

    Herrera, Higmar

    2006-09-08

    This work proposes the use of the Matlab environment to obtain the treatment dose based on the reported data by Krishnaswamy and Liu et al. The comparison with reported measurements is showed for the Amersham source model. For the 3M source model, measurements with TLDs and a Monte Carlo simulation are compared to the data obtained by Matlab. The difference for the Amersham model is well under the 15% recommended by the IAEA and for the 3M model, although the difference is greater, the results are consistent. The good agreement to the reported data allows the Matlab calculations to be used in daily brachytherapy treatments.

  16. Ruby-based inorganic scintillation detectors for 192Ir brachytherapy

    NASA Astrophysics Data System (ADS)

    Kertzscher, Gustavo; Beddar, Sam

    2016-11-01

    We tested the potential of ruby inorganic scintillation detectors (ISDs) for use in brachytherapy and investigated various unwanted luminescence properties that may compromise their accuracy. The ISDs were composed of a ruby crystal coupled to a poly(methyl methacrylate) fiber-optic cable and a charge-coupled device camera. The ISD also included a long-pass filter that was sandwiched between the ruby crystal and the fiber-optic cable. The long-pass filter prevented the Cerenkov and fluorescence background light (stem signal) induced in the fiber-optic cable from striking the ruby crystal, which generates unwanted photoluminescence rather than the desired radioluminescence. The relative contributions of the radioluminescence signal and the stem signal were quantified by exposing the ruby detectors to a high-dose-rate brachytherapy source. The photoluminescence signal was quantified by irradiating the fiber-optic cable with the detector volume shielded. Other experiments addressed time-dependent luminescence properties and compared the ISDs to commonly used organic scintillator detectors (BCF-12, BCF-60). When the brachytherapy source dwelled 0.5 cm away from the fiber-optic cable, the unwanted photoluminescence was reduced from  >5% to  <1% of the total signal as long as the ISD incorporated the long-pass filter. The stem signal was suppressed with a band-pass filter and was  <3% as long as the source distance from the scintillator was  <7 cm. Some ruby crystals exhibited time-dependent luminescence properties that altered the ruby signal by  >5% within 10 s from the onset of irradiation and after the source had retracted. The ruby-based ISDs generated signals of up to 20 times that of BCF-12-based detectors. The study presents solutions to unwanted luminescence properties of ruby-based ISDs for high-dose-rate brachytherapy. An optic filter should be sandwiched between the ruby crystal and the fiber-optic cable to suppress the

  17. [Endobronchial brachytherapy: state of the art in 2013].

    PubMed

    Derhem, N; Sabila, H; Mornex, F

    2013-04-01

    Endobronchial brachytherapy is an invasive technique, which allows localizing radioactive sources at the tumour contact. Therefore, high doses are administered to tumour while healthy tissues can be spared. Initially dedicated to a palliative setting, improvements helped reaching 60 to 88% symptoms alleviation and 30 to 100% of endoscopic macroscopic response. New diagnostic techniques and early diagnosis extended the indications to a curative intent: endoluminal primitive tumour, post radiation endobronchial recurrence, inoperable patients. CT-based dosimetry is a keypoint to optimize treatment quality and to minimize potential side effects, making this treatment a safe and efficient technique for specific indications.

  18. Radiological response of ceramic and polymeric devices for breast brachytherapy.

    PubMed

    Nogueira, Luciana Batista; de Campos, Tarcisio Passos Ribeiro

    2012-04-01

    In the present study, the radiological visibility of ceramic and polymeric devices implanted in breast phantom was investigated for future applications in brachytherapy. The main goal was to determine the radiological viability of ceramic and polymeric devices in vitro by performing simple radiological diagnostic methods such as conventional X-ray analysis and mammography due to its easy access to the population. The radiological response of ceramic and polymeric devices implanted in breast phantom was determined using conventional X-ray, mammography and CT analysis.

  19. Growth delay effect of combined interstitial hyperthermia and brachytherapy in a rat solid tumor model.

    PubMed

    Papadopoulos, D; Kimler, B F; Estes, N C; Durham, F J

    1989-01-01

    The rat mammary AC33 solid tumor model was used to investigate the efficacy of interstitial hyperthermia and/or brachytherapy. Subcutaneous flank tumors were heated with an interstitial microwave (915 MHz) antenna to a temperature of 43 +/- 0.5 degrees C for 45 min for two treatments, three days apart, and/or implanted with Ir-192 seeds for three days (-25 Gy tumor dose). Following treatments, tumors were measured 2 to 3 times per week. Hyperthermia alone produced a modest delay in tumor volume regrowth, while brachytherapy was substantially more effective. The combination produced a improvement in tumor regrowth delay compared to brachytherapy alone.

  20. Teaching Object Permanence: An Action Research Study

    ERIC Educational Resources Information Center

    Bruce, Susan M.; Vargas, Claudia

    2013-01-01

    "Object permanence," also known as "object concept" in the field of visual impairment, is one of the most important early developmental milestones. The achievement of object permanence is associated with the onset of representational thought and language. Object permanence is important to orientation, including the recognition of landmarks.…

  1. 21 CFR 886.4445 - Permanent magnet.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Permanent magnet. 886.4445 Section 886.4445 Food... DEVICES OPHTHALMIC DEVICES Surgical Devices § 886.4445 Permanent magnet. (a) Identification. A permanent magnet is a nonelectric device that generates a magnetic field intended to find and remove...

  2. 21 CFR 886.4445 - Permanent magnet.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Permanent magnet. 886.4445 Section 886.4445 Food... DEVICES OPHTHALMIC DEVICES Surgical Devices § 886.4445 Permanent magnet. (a) Identification. A permanent magnet is a nonelectric device that generates a magnetic field intended to find and remove...

  3. 21 CFR 886.4445 - Permanent magnet.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Permanent magnet. 886.4445 Section 886.4445 Food... DEVICES OPHTHALMIC DEVICES Surgical Devices § 886.4445 Permanent magnet. (a) Identification. A permanent magnet is a nonelectric device that generates a magnetic field intended to find and remove...

  4. Permanent-File-Validation Utility Computer Program

    NASA Technical Reports Server (NTRS)

    Derry, Stephen D.

    1988-01-01

    Errors in files detected and corrected during operation. Permanent File Validation (PFVAL) utility computer program provides CDC CYBER NOS sites with mechanism to verify integrity of permanent file base. Locates and identifies permanent file errors in Mass Storage Table (MST) and Track Reservation Table (TRT), in permanent file catalog entries (PFC's) in permit sectors, and in disk sector linkage. All detected errors written to listing file and system and job day files. Program operates by reading system tables , catalog track, permit sectors, and disk linkage bytes to vaidate expected and actual file linkages. Used extensively to identify and locate errors in permanent files and enable online correction, reducing computer-system downtime.

  5. Impact of Radionuclide Physical Distribution on Brachytherapy Dosimetry Parameters

    SciTech Connect

    Rivard, M.J.; Kirk, B.L.; Leal, L.C.

    2005-01-15

    Radiation dose distributions of brachytherapy sources are generally characterized with the assumption that all internal components are equally radioactive. Autoradiographs and discussions with source manufacturers indicated this assumption of the radionuclide physical distribution may be invalid. Consequently, clinical dose distributions would be in error when not accounting for these internal variations. Many implants use brachytherapy sources with four {sup 125}I resin beads and two radiopaque markers used for imaging. Monte Carlo methods were used to determine dose contributions from each of the resin beads. These contributions were compared with those from an idealized source having a uniform physical distribution. Upon varying the {sup 125}I physical distribution while retaining the same overall radioactivity, the dose distribution along the transverse plane remained constant within 5% for r > 0.5 cm. For r {<=} 0.5 cm, relative positioning of the resin beads dominated the shielding effects, and dose distributions varied up to a factor of 3 at r = 0.05 cm. For points off the transverse plane, comparisons of the uniform and nonuniform dose distributions produced larger variations. Shielding effects within the capsule were virtually constant along the source long axis and demonstrated that anisotropy variations among the four resin beads were dependent on internal component positioning.

  6. Application of a diamond detector to brachytherapy dosimetry.

    PubMed

    Rustgi, S N

    1998-08-01

    The feasibility of using a diamond detector for the dosimetry of brachytherapy sources has been investigated. A high-activity 192Ir source was selected for this purpose. The dosimetric characteristics measured included the photon fluence anisotropy in air, transverse dose profiles in planes parallel to the plane containing the HDR source and isodose distributions. The 'in-air' anisotropy of the photon fluence relative to seed orientation was measured at 5 and 10 cm from the source centre and compared with TLD measurements. Transverse dose distributions in planes parallel to the plane containing the source long axis were measured in a water phantom and compared with calculations performed with a treatment planning system. Isodose distributions were also measured in several planes around the 192Ir source. Measurements on two sources indicate that the 'in-air' photon fluence anisotropy measured by the diamond detector and the TLDs is very similar. Dose profiles measured at several distances from the source are also found to be in good agreement with the calculated dose profiles and isodose distributions. Results of this feasibility study indicate that the diamond detector, with its excellent spatial resolution and nearly tissue equivalent and isotropic radiation response, is an appropriate detector for dose measurements around brachytherapy sources.

  7. 2D/3D registration algorithm for lung brachytherapy

    SciTech Connect

    Zvonarev, P. S.; Farrell, T. J.; Hunter, R.; Wierzbicki, M.; Hayward, J. E.; Sur, R. K.

    2013-02-15

    Purpose: A 2D/3D registration algorithm is proposed for registering orthogonal x-ray images with a diagnostic CT volume for high dose rate (HDR) lung brachytherapy. Methods: The algorithm utilizes a rigid registration model based on a pixel/voxel intensity matching approach. To achieve accurate registration, a robust similarity measure combining normalized mutual information, image gradient, and intensity difference was developed. The algorithm was validated using a simple body and anthropomorphic phantoms. Transfer catheters were placed inside the phantoms to simulate the unique image features observed during treatment. The algorithm sensitivity to various degrees of initial misregistration and to the presence of foreign objects, such as ECG leads, was evaluated. Results: The mean registration error was 2.2 and 1.9 mm for the simple body and anthropomorphic phantoms, respectively. The error was comparable to the interoperator catheter digitization error of 1.6 mm. Preliminary analysis of data acquired from four patients indicated a mean registration error of 4.2 mm. Conclusions: Results obtained using the proposed algorithm are clinically acceptable especially considering the complications normally encountered when imaging during lung HDR brachytherapy.

  8. Observations on rotating needle insertions using a brachytherapy robot

    NASA Astrophysics Data System (ADS)

    Meltsner, M. A.; Ferrier, N. J.; Thomadsen, B. R.

    2007-09-01

    A robot designed for prostate brachytherapy implantations has the potential to greatly improve treatment success. Much of the research in robotic surgery focuses on measuring accuracy. However, there exist many factors that must be optimized before an analysis of needle placement accuracy can be determined. Some of these parameters include choice of the needle type, insertion velocity, usefulness of the rotating needle and rotation speed. These parameters may affect the force at which the needle interacts with the tissue. A reduction in force has been shown to decrease the compression of the prostate and potentially increase the accuracy of seed position. Rotating the needle as it is inserted may reduce frictional forces while increasing accuracy. However, needle rotations are considered to increase tissue damage due to the drilling nature of the insertion. We explore many of the factors involved in optimizing a brachytherapy robot, and the potential effects each parameter may have on the procedure. We also investigate the interaction of rotating needles in gel and suggest the rotate-cannula-only method of conical needle insertion to minimize any tissue damage while still maintaining the benefits of reduced force and increased accuracy.

  9. Prostate brachytherapy training with simulated ultrasound and fluoroscopy images.

    PubMed

    Goksel, Orcun; Sapchuk, Kirill; Morris, William J; Salcudean, Septimiu E

    2013-04-01

    In this paper, a novel computer-based virtual training system for prostate brachytherapy is presented. This system incorporates, in a novel way, prior methodologies of ultrasound image synthesis and haptic transrectal ultrasound (TRUS) transducer interaction in a complete simulator that allows a trainee to maneuver the needle and the TRUS, to see the resulting patient-specific images and feel the interaction forces. The simulated TRUS images reflect the volumetric tissue deformation and comprise validated appearance models for the needle and implanted seeds. Rendered haptic forces use validated models for needle shaft flexure and friction, tip cutting, and deflection due to bevel. This paper also presents additional new features that make the simulator complete, in the sense that all aspects of the brachytherapy procedure as practiced at many cancer centers are simulated, including simulations of seed unloading, fluoroscopy imaging, and transversal/sagittal TRUS plane switching. For real-time rendering, methods for fast TRUS-needle-seed image formation are presented. In addition, the simulator computes real-time dosimetry, allowing a trainee to immediately see the consequence of planning changes. The simulation is also patient specific, as it allows the user to import the treatment plan for a patient together with the imaging data in order for a physician to practice an upcoming procedure or for a medical resident to train using typical implant scenarios or rarely encountered cases.

  10. Current status and perspectives of brachytherapy for cervical cancer.

    PubMed

    Toita, Takafumi

    2009-02-01

    Standard definitive radiotherapy for cervical cancer consists of whole pelvic external beam radiotherapy (EBRT) and intracavitary brachytherapy (ICBT). In Japan, high-dose-rate ICBT (HDR-ICBT) has been utilized in clinical practice for more than 40 years. Several randomized clinical trials demonstrated that HDR-ICBT achieved comparative outcomes, both for pelvic control and incidences of late complications, to low-dose-rate (LDR) ICBT. In addition, HDR-ICBT has some potential advantages over LDR-ICBT, leading to further improvement in treatment results. Prior to the current computer planning systems, some excellent treatment planning concepts were established. At present, systems modified from these concepts, or novel approaches, such as image-guided brachytherapy (IGBT) are under investigation. One serious problem to be solved in HDR-ICBT for cervical cancer is that of the discrepancy in standard treatment schedules for combination HDR-ICBT and EBRT between the United States and Japan. Prospective studies are ongoing to assess the efficacy and toxicity of the Japanese schedule.

  11. Dosimetric Study of a Low-Dose-Rate Brachytherapy Source

    NASA Astrophysics Data System (ADS)

    Rodríguez-Villafuerte, M.; Arzamendi, S.; Díaz-Perches, R.

    Carcinoma of the cervix is the most common malignancy - in terms of both incidence and mortality - in Mexican women. Low dose rate (LDR) intracavitary brachytherapy is normally prescribed for the treatment of this disease to the vast majority of patients attending public hospitals in our country. However, most treatment planning systems being used in these hospitals still rely on Sievert integral dose calculations. Moreover, experimental verification of dose distributions are hardly ever done. In this work we present a dosimetric characterisation of the Amersham CDCS-J 137Cs source, an LDR brachytherapy source commonly used in Mexican hospitals. To this end a Monte Carlo simulation was developed, that includes a realistic description of the internal structure of the source embedded in a scattering medium. The Monte Carlo results were compared to experimental measurements of dose distributions. A lucite phantom with the same geometric characteristics as the one used in the simulation was built. Dose measurements were performed using thermoluminescent dosimeters together with commercial RadioChromic dye film. A comparison between our Monte Carlo simulation, the experimental data, and results reported in the literature is presented.

  12. Thermoluminescence dosimetry measurements of brachytherapy sources in liquid water

    SciTech Connect

    Tailor, Ramesh; Tolani, Naresh; Ibbott, Geoffrey S.

    2008-09-15

    Radiation therapy dose measurements are customarily performed in liquid water. The characterization of brachytherapy sources is, however, generally based on measurements made with thermoluminescence dosimeters (TLDs), for which contact with water may lead to erroneous readings. Consequently, most dosimetry parameters reported in the literature have been based on measurements in water-equivalent plastics, such as Solid Water. These previous reports employed a correction factor to transfer the dose measurements from a plastic phantom to liquid water. The correction factor most often was based on Monte Carlo calculations. The process of measuring in a water-equivalent plastic phantom whose exact composition may be different from published specifications, then correcting the results to a water medium leads to increased uncertainty in the results. A system has been designed to enable measurements with TLDs in liquid water. This system, which includes jigs to support water-tight capsules of lithium fluoride in configurations suitable for measuring several dosimetric parameters, was used to determine the correction factor from water-equivalent plastic to water. Measurements of several {sup 125}I and {sup 131}Cs prostate brachytherapy sources in liquid water and in a Solid Water phantom demonstrated a correction factor of 1.039{+-}0.005 at 1 cm distance. These measurements are in good agreement with a published value of this correction factor for an {sup 125}I source.

  13. Brachytherapy dosimetry parameters calculated for a 131Cs source.

    PubMed

    Rivard, Mark J

    2007-02-01

    A comprehensive analysis of the IsoRay Medical model CS-1 Rev2 131Cs brachytherapy source was performed. Dose distributions were simulated using Monte Carlo methods (MCNP5) in liquid water, Solid Water, and Virtual Water spherical phantoms. From these results, the in-water brachytherapy dosimetry parameters have been determined, and were compared with those of Murphy et al. [Med. Phys. 31, 1529-1538 (2004)] using measurements and simulations. Our results suggest that calculations obtained using erroneous cross-section libraries should be discarded as recommended by the 2004 AAPM TG-43U1 report. Our Mclambda value of 1.046+/-0.019 cGy h(-1) U(-1) is within 1.3% of that measured by Chen et al. [Med. Phys. 32, 3279-3285 (2005)] using TLDs and the calculated results of Wittman and Fisher [Med. Phys. 34, 49-54 (2007)] using MCNP5. Using the discretized energy approach of Rivard [Appl. Radiat. Isot. 55, 775-782 (2001)] to ascertain the impact of individual 131Cs photons on radial dose function and anisotropy functions, there was virtual equivalence of results for 29.461< or =Egamma< or = 34.419 keV and for a mono-energetic 30.384 keV photon source. Comparisons of radial dose function and 2D anisotropy function data are also included, and an analysis of material composition and cross-section libraries was performed.

  14. Brachytherapy, A viable option of globe salvage in treatment of large ciliary body melanocytoma

    PubMed Central

    Shanmugam, Mahesh P.; Saxena, Manish; Ramanjulu, Rajesh; Tekwani, Pradeep

    2014-01-01

    We report a case of large histopathologically proven melanocytoma of the ciliary body in a 15-year-old male, presented with rapid extraocular growth following incisional biopsy with scleral patch graft. We chose brachytherapy with Ruthenium 106 plaque over enucleation as the later was refused by the parents. The initial apical height of the tumor was 14.2 mm on ultrasonography. Two weeks after brachytherapy, the mass regressed to a size of 8.1 mm and 1 year later to 6.7 mm. This is the first case report showing the response of brachytherapy to ciliary body melanocytoma, which results in ocular and visual acuity salvation with considerable decreased in size of the tumor. The authors conclude that brachytherapy is an option in the management of non-resectable melanocytoma of the ciliary body. PMID:25370406

  15. Penile cancer brachytherapy HDR mould technique used at the Holycross Cancer Center

    PubMed Central

    Kubicka-Mendak, Iwona; Łyczek, Jarosław; Pawłowski, Piotr; Stawiarska, Iwona; Miedzinska, Joanna; Banatkiewicz, Paweł; Łaskawska-Wiatr, Aldona; Wittych, Justyna

    2011-01-01

    The aim of this pictorial essay is to present the mould based HDR brachytherapy technique used at the Holycross Cancer Center for penile cancer patients. We use images to describe this method step by step. PMID:23346132

  16. Penile cancer brachytherapy HDR mould technique used at the Holycross Cancer Center.

    PubMed

    Matys, Robert; Kubicka-Mendak, Iwona; Lyczek, Jarosław; Pawłowski, Piotr; Stawiarska, Iwona; Miedzinska, Joanna; Banatkiewicz, Paweł; Laskawska-Wiatr, Aldona; Wittych, Justyna

    2011-12-01

    The aim of this pictorial essay is to present the mould based HDR brachytherapy technique used at the Holycross Cancer Center for penile cancer patients. We use images to describe this method step by step.

  17. The trail of the development of high-dose-rate brachytherapy for cervical cancer in Japan.

    PubMed

    Inoue, Toshihiko

    2003-07-01

    The differences in radiotherapeutic treatment systems for cervical cancer between the United States and Japan can be attributed either to the tolerance of high-risk organs, or dosimetry itself. High-dose-rate (HDR) brachytherapy is the standard treatment for uterine cervix carcinoma in Japan. In addition, HDR Co-60 afterloading machines have been gradually replaced with Ir-192 micro-source afterloading machines during the past ten years. This implies that it has now become impossible to conduct a prospective comparative study of HDR versus low-dose-rate (LDR) brachytherapy for cervical cancer in Japan. An examination of the history of HDR intracavitary radiotherapy for uterine cervix carcinoma in Japan led us to the conclusion that HDR intracavitary brachytherapy for the treatment of cervical cancer is as effective as LDR intracavitary brachytherapy in terms of both survival and complications. In Japan, studies on the former can be drawn from a long experience of more than 35 years.

  18. Feasibility of calibrating elongated brachytherapy sources using a well-type ionization chamber

    SciTech Connect

    Meigooni, Ali S.; Awan, Shahid B.; Dou, Kai

    2006-11-15

    Recently, elongated brachytherapy sources (active length >1 cm) have become commercially available for interstitial prostate implants. These sources were introduced to improve the quality of brachytherapy procedures by eliminating the migration and seed bunching associated with loose seed-type implants. However, the inability to calibrate elongated brachytherapy sources with the Wide-Angle Free-Air Chamber (WAFAC) used by the National Institute of Standards and Technology (NIST) hinders the experimental determination of dosimetric parameters of these source types. In order to resolve this shortcoming, an interim solution has been introduced for calibration of elongated brachytherapy sources using a commercially available well-type ionization chamber. The feasibility of this procedure was examined by calibrating RadioCoil{sup Tm} {sup 103}Pd sources with active lengths ranging from 1 to 7 cm.

  19. FIGO stage IB1 cervical carcinoma: Place and principles of brachytherapy.

    PubMed

    Huertas, A; Oldrini, S; Nesseler, J-P; Courrech, F; Rétif, P; Charra-Brunaud, C; Peiffert, D

    2017-02-20

    The treatment of cervical cancers according to FIGO staging is well defined. For FIGO stage IB2 or more, chemoradiotherapy followed by uterovaginal brachytherapy boost is the standard treatment. Surgery is the preferred choice for less advanced tumors. However, most French institutions propose preoperative brachytherapy followed by hysterectomy with pelvic lymphadenectomy for FIGO stage IB1 tumors over 2cm. Brachytherapy is also used for the boost after adjuvant pelvic external beam radiotherapy. Tridimensional dosimetry with optimization allows better treatment planning, delivering high doses to target volumes with limited irradiation to the organs at risk. We will discuss the indications of brachytherapy for FIGO stage IB1 tumors and the principles of pulsed-dose rate and high-dose rate techniques.

  20. Method of making permanent magnets

    DOEpatents

    McCallum, R.W.; Dennis, K.W.; Lograsso, B.K.; Anderson, I.E.

    1993-09-07

    A method for making an isotropic permanent magnet comprises atomizing a melt of a rare earth-transition metal alloy (e.g., an Nd--Fe--B alloy enriched in Nd and B) under conditions to produce protectively coated, rapidly solidified, generally spherical alloy particles. Wherein a majority of the particles are produced/size classified within a given size fraction (e.g., 5 to 40 microns diameter) exhibiting optimum as-atomized magnetic properties and subjecting the particles to concurrent elevated temperature and elevated isotropic pressure for a time effective to yield a densified, magnetically isotropic magnet compact having enhanced magnetic properties and mechanical properties. 13 figures.

  1. Method of making permanent magnets

    DOEpatents

    McCallum, R. William; Dennis, Kevin W.; Lograsso, Barbara K.; Anderson, Iver E.

    1993-09-07

    A method for making an isotropic permanent magnet comprises atomizing a melt of a rare earth-transition metal alloy (e.g., an Nd--Fe--B alloy enriched in Nd and B) under conditions to produce protectively coated, rapidly solidified, generally spherical alloy particles wherein a majority of the particles are produced/size classified within a given size fraction (e.g., 5 to 40 microns diameter) exhibiting optimum as-atomized magnetic properties and subjecting the particles to concurrent elevated temperature and elevated isotropic pressure for a time effective to yield a densified, magnetically isotropic magnet compact having enhanced magnetic properties and mechanical properties.

  2. Comparison of dose calculation methods for brachytherapy of intraocular tumors

    SciTech Connect

    Rivard, Mark J.; Chiu-Tsao, Sou-Tung; Finger, Paul T.; Meigooni, Ali S.; Melhus, Christopher S.; Mourtada, Firas; Napolitano, Mary E.; Rogers, D. W. O.; Thomson, Rowan M.; Nath, Ravinder

    2011-01-15

    Purpose: To investigate dosimetric differences among several clinical treatment planning systems (TPS) and Monte Carlo (MC) codes for brachytherapy of intraocular tumors using {sup 125}I or {sup 103}Pd plaques, and to evaluate the impact on the prescription dose of the adoption of MC codes and certain versions of a TPS (Plaque Simulator with optional modules). Methods: Three clinical brachytherapy TPS capable of intraocular brachytherapy treatment planning and two MC codes were compared. The TPS investigated were Pinnacle v8.0dp1, BrachyVision v8.1, and Plaque Simulator v5.3.9, all of which use the AAPM TG-43 formalism in water. The Plaque Simulator software can also handle some correction factors from MC simulations. The MC codes used are MCNP5 v1.40 and BrachyDose/EGSnrc. Using these TPS and MC codes, three types of calculations were performed: homogeneous medium with point sources (for the TPS only, using the 1D TG-43 dose calculation formalism); homogeneous medium with line sources (TPS with 2D TG-43 dose calculation formalism and MC codes); and plaque heterogeneity-corrected line sources (Plaque Simulator with modified 2D TG-43 dose calculation formalism and MC codes). Comparisons were made of doses calculated at points-of-interest on the plaque central-axis and at off-axis points of clinical interest within a standardized model of the right eye. Results: For the homogeneous water medium case, agreement was within {approx}2% for the point- and line-source models when comparing between TPS and between TPS and MC codes, respectively. For the heterogeneous medium case, dose differences (as calculated using the MC codes and Plaque Simulator) differ by up to 37% on the central-axis in comparison to the homogeneous water calculations. A prescription dose of 85 Gy at 5 mm depth based on calculations in a homogeneous medium delivers 76 Gy and 67 Gy for specific {sup 125}I and {sup 103}Pd sources, respectively, when accounting for COMS-plaque heterogeneities. For off

  3. Highly efficient method for production of radioactive silver seed cores for brachytherapy.

    PubMed

    Cardoso, Roberta Mansini; de Souza, Carla Daruich; Rostelato, Maria Elisa Chuery Martins; Araki, Koiti

    2017-02-01

    A simple and highly efficient (shorter reaction time and almost no rework) method for production of iodine based radioactive silver seed cores for brachytherapy is described. The method allows almost quantitative deposition of iodine-131 on dozens of silver substrates at once, with even distribution of activity per core and insignificant amounts of liquid and solid radioactive wastes, allowing the fabrication of cheaper radioactive iodine seeds for brachytherapy.

  4. Preparation of (103)Pd brachytherapy seeds by electroless plating of (103)Pd onto carbon bars.

    PubMed

    Li, Zhong-Yong; Gao, Hui-Bo; Deng, Xue-Song; Zhou, Leng; Zhang, Wen-Hui; Han, Lian-Ge; Jin, Xiao-Hai; Cui, Hai-Ping

    2015-09-01

    A method for preparing (103)Pd brachytherapy seeds is reported. The key of the method was to deposit (103)Pd onto carbon bars by electroless plating so as to prepare source cores. After each carbon bar with (103)Pd was sealed in a titanium capsule, the (103)Pd seeds were fabricated. This paper provides valuable experiences and data for the preparation of (103)Pd brachytherapy seeds.

  5. Temporal relationship between prostate brachytherapy and the diagnosis of colorectal cancer

    SciTech Connect

    Gutman, Sarah A.; Merrick, Gregory S. . E-mail: gmerrick@urologicresearchinstitute.org; Butler, Wayne M.; Wallner, Kent E.; Allen, Zachariah A.; Galbreath, Robert W.; Adamovich, Edward

    2006-09-01

    Purpose: To identify the location of pretreatment and posttreatment colorectal malignancies and posttreatment colorectal polyps in patients with clinically localized prostate cancer managed with brachytherapy. Methods and Materials: From April 1995 through July 2004, 1,351 consecutive patients underwent brachytherapy for clinical stage T1b-T3a (American Joint Committee on Cancer, 2002) prostate cancer. Supplemental external beam radiotherapy (XRT) was administered to 699 patients. The median follow-up was 4.6 years. Operative and pathology reports were reviewed for all patients with pretreatment and posttreatment colorectal cancer and posttreatment colorectal polyps. Multiple parameters were evaluated for the development of colorectal cancer or colorectal polyps. Results: Colorectal cancer was diagnosed in 23 and 25 patients before and after prostate brachytherapy, respectively. No differences were identified in the distribution of colorectal cancers either before or after treatment (3 and 4 rectal cancers in the pre- and postbrachytherapy cohorts). Thirty-five of the 48 colorectal cancers (73%) were diagnosed within 5 years of brachytherapy with a peak incidence 1 year after brachytherapy. One hundred ninety-two colorectal polyps were diagnosed after brachytherapy, 160 (83%) occurred within 4 years of brachytherapy, and only 27 (14%) were located in the rectum. In multivariate Cox regression analysis, prostate D{sub 9} (minimum percentage of the dose covering 90% of the target volume) predicted for posttreatment colorectal cancer. Rectal polyps were most closely related to patient age and percent positive biopsies, whereas sigmoid/colon polyps were best predicted by patient age, planning volume, and supplemental XRT. Conclusions: Colorectal cancer was diagnosed with equal frequency before and after brachytherapy with comparable geographic distributions. In addition, the vast majority of postbrachytherapy colorectal polyps were located beyond the confines of the

  6. Evaluation of neuropathic pain occurring after high-dose-rate interstitial brachytherapy of oral tongue

    PubMed Central

    Sharma, Suresh C.; Kapoor, Rakesh; Ahuja, Chirag K.; Oinam, Arun S.; Ghoshal, Sushmita

    2015-01-01

    Purpose To recognize neuropathic pain as a complication of high-dose-rate (HDR) interstitial brachytherapy of oral tongue and to evaluate the possible causes of neuropathy. Material and methods Twenty one patients who underwent interstitial brachytherapy for early cancer of oral tongue were evaluated. The patients either underwent primary brachytherapy (42-48 Gy at 3-4 Gy/fraction) or a boost (18-24 Gy at 3 Gy/fraction) after external radiation to 40 Gy. Lingual nerve was the nerve concerned and the sublingual space (SLS) was contoured as its surrogate. Dosimetric parameters were correlated with onset of pain. Results Ten patients out of 21 (47.61%) developed painful neuropathy. Five patients of six (5/6) who underwent primary brachytherapy developed neuropathy. Five out of 15 (5/15) patients who underwent brachytherapy as a boost developed neuropathy. The patients who underwent primary brachytherapy were ten times more likely to develop neuropathy. Among the patients receiving boost treatment, the equivalent dose at 2 Gy/fraction (EQD2) to 2 cc of SLS was higher (39.25 Gy) in the patients who developed pain compared to those without pain (10.29 Gy). Conclusions This is the first report to recognize neuropathic pain as a complication of HDR brachytherapy of oral tongue. Patients undergoing primary brachytherapy were more likely to develop pain. Among other factors like dose to SLS, number of catheters, size of the primary tumor, and the dose rate, only dose to 2 cc of the SLS correlated with onset of pain. The SLS (containing the lingual nerve) may be considered an organ at risk to prevent the occurrence of this complication. PMID:26034495

  7. Microfocus X-ray imaging of the internal geometry of brachytherapy seeds.

    PubMed

    Hasegawa, Tomoyuki; Hanada, Takashi; Yorozu, Atsunori; Ito, Hidetaka; Masuda, Shinji; Kawahara, Maki; Yogo, Katsunori; Hayakawa, Kazushige

    2014-04-01

    Precise and reliable geometrical data on the internal structure of seeds are indispensable for dosimetric calculation in brachytherapy. We used a novel microfocus X-ray imaging technique for observing the internal structure of brachytherapy seeds. Two popular (125)I seed models were evaluated. Obtained high precision images enabled us to observe the internal structure of seeds qualitatively. Geometrical size parameters were evaluated quantitatively with uncertainty of 0.01-0.04 mm (k=2).

  8. High Dose-Rate Versus Low Dose-Rate Brachytherapy for Lip Cancer

    SciTech Connect

    Ghadjar, Pirus; Bojaxhiu, Beat; Simcock, Mathew; Terribilini, Dario; Isaak, Bernhard; Gut, Philipp; Wolfensberger, Patrick; Broemme, Jens O.; Geretschlaeger, Andreas; Behrensmeier, Frank; Pica, Alessia; Aebersold, Daniel M.

    2012-07-15

    Purpose: To analyze the outcome after low-dose-rate (LDR) or high-dose-rate (HDR) brachytherapy for lip cancer. Methods and Materials: One hundred and three patients with newly diagnosed squamous cell carcinoma of the lip were treated between March 1985 and June 2009 either by HDR (n = 33) or LDR brachytherapy (n = 70). Sixty-eight patients received brachytherapy alone, and 35 received tumor excision followed by brachytherapy because of positive resection margins. Acute and late toxicity was assessed according to the Common Terminology Criteria for Adverse Events 3.0. Results: Median follow-up was 3.1 years (range, 0.3-23 years). Clinical and pathological variables did not differ significantly between groups. At 5 years, local recurrence-free survival, regional recurrence-free survival, and overall survival rates were 93%, 90%, and 77%. There was no significant difference for these endpoints when HDR was compared with LDR brachytherapy. Forty-two of 103 patients (41%) experienced acute Grade 2 and 57 of 103 patients (55%) experienced acute Grade 3 toxicity. Late Grade 1 toxicity was experienced by 34 of 103 patients (33%), and 5 of 103 patients (5%) experienced late Grade 2 toxicity; no Grade 3 late toxicity was observed. Acute and late toxicity rates were not significantly different between HDR and LDR brachytherapy. Conclusions: As treatment for lip cancer, HDR and LDR brachytherapy have comparable locoregional control and acute and late toxicity rates. HDR brachytherapy for lip cancer seems to be an effective treatment with acceptable toxicity.

  9. Targeting MRS-Defined Dominant Intraprostatic Lesions with Inverse-Planned High Dose Rate Brachytherapy

    DTIC Science & Technology

    2010-06-01

    prostate and the protection to the urethra , rectum, and bladder for prostate cancer patients treated with High Dose Rate (HDR) brachytherapy. The multi...and the protection to the urethra , rectum and bladder for prostate cancer patients treated with HDR brachytherapy. BODY The feasibility...of the DIL without compromising the dose coverage of the prostate and the protection to the urethra , rectum, and bladder for prostate cancer patients

  10. GEC-ESTRO recommendations for brachytherapy for head and neck squamous cell carcinomas.

    PubMed

    Mazeron, Jean-Jacques; Ardiet, Jean-Michel; Haie-Méder, Christine; Kovács, György; Levendag, Peter; Peiffert, Didier; Polo, Alfredo; Rovirosa, Angels; Strnad, Vratislav

    2009-05-01

    Both primary and recurrent squamous cell carcinoma of the head and neck are classic indications for brachytherapy. A high rate of local tumor control at the cost of limited morbidity can be achieved with brachytherapy through good patient selection, meticulous source implantation and careful treatment planning. However, no randomized trials have been performed, and there is scant evidence in the literature especially regarding practical clinical recommendations for brachytherapy for head and neck subsites. The Head and Neck Working Group of the European Brachytherapy Group (Groupe Européen de Curiethérapie-European Society for Therapeutic Radiology and Oncology (GEC-ESTRO) therefore decided to formulate the present consensus recommendations for low-dose rate, pulsed-dose rate and high-dose rate brachytherapy. The use of brachytherapy in combination with external beam radiotherapy and/or surgery is also covered as well as the use of brachytherapy in previously irradiated patients. Given the paucity of evidence in the literature, these recommendations are mainly based on clinical experience accumulated by the members of the working group over several decades and the respective publications. The recommendations cover in a general part (1) patient selection, the pre-treatment work up and patient care, (2) treatment strategy, (3) target definition, (4) implant techniques, (5) dose and dose rate prescription, (6) treatment planning and reporting, (7) treatment monitoring (8) catheter removal, and (9) post-treatment patient care and follow-up. The recommendations are then specified for the classical brachytherapy tumor sites following an analogue more focussed structure (patient selection, implant technique, target definition, dose and dose rate prescription, results): lip, oral mucosa, mobile tongue, floor of mouth, oropharynx, nasopharynx, paranasal sinuses.

  11. Effect of brachytherapy technique and patient characteristics on cervical cancer implant dosimetry

    SciTech Connect

    Anker, Christopher J.; O'Donnell, Kristen; Boucher, Kenneth M.; Gaffney, David K.

    2013-01-01

    Our purpose was to evaluate the relationship between brachytherapy technique and patient characteristics on dose to organs-at-risk (OARs) in patients undergoing high dose rate (HDR) brachytherapy for cervical cancer. From 1998 to 2008, 31 patients with cervical cancer with full dosimetric data were identified who received definitive external-beam radiation and HDR brachytherapy with tandem and ovoid applicators. Doses were recorded at point A, the International Commission on Radiation Units and Measurements (ICRU)-38 rectal point, the ICRU-38 bladder point, the vaginal surface, and the pelvic sidewall. Generalized estimating equations were used to determine the significance of changes in OAR to point A dose ratios with differences in brachytherapy technique or patient characteristics. Patients underwent a median of 5 brachytherapy procedures (range, 3 to 5), with a total of 179 procedures for 31 patients. For all brachytherapy treatments, the average ratios between the doses for the rectal, bladder, vaginal surface, and pelvic sidewall reference points to those at point A were 0.49, 0.59, 1.15, and 0.17, respectively. In general, decreased OAR dose was associated with a lower stage, younger age, increased ovoid size, increased tandem length, and earlier implant number. Increased tandem curvature significantly increased bladder dose and decreased rectal dose. Intravenous anesthesia usage was not correlated with improved dosimetry. This study allowed identification of patient and procedure characteristics influencing OAR dosing. Although the advent of 3-dimensional (3D) image-guided brachytherapy will bring new advances in treatment optimization, the actual technique involved at the time of the brachytherapy implant procedure will remain important.

  12. High-performance permanent magnets.

    PubMed

    Goll, D; Kronmüller, H

    2000-10-01

    High-performance permanent magnets (pms) are based on compounds with outstanding intrinsic magnetic properties as well as on optimized microstructures and alloy compositions. The most powerful pm materials at present are RE-TM intermetallic alloys which derive their exceptional magnetic properties from the favourable combination of rare earth metals (RE = Nd, Pr, Sm) with transition metals (TM = Fe, Co), in particular magnets based on (Nd.Pr)2Fe14B and Sm2(Co,Cu,Fe,Zr)17. Their development during the last 20 years has involved a dramatic improvement in their performance by a factor of > 15 compared with conventional ferrite pms therefore contributing positively to the ever-increasing demand for pms in many (including new) application fields, to the extent that RE-TM pms now account for nearly half of the worldwide market. This review article first gives a brief introduction to the basics of ferromagnetism to confer an insight into the variety of (permanent) magnets, their manufacture and application fields. We then examine the rather complex relationship between the microstructure and the magnetic properties for the two highest-performance and most promising pm materials mentioned. By using numerical micromagnetic simulations on the basis of the Finite Element technique the correlation can be quantitatively predicted, thus providing a powerful tool for the further development of optimized high-performance pms.

  13. High-performance permanent magnets

    NASA Astrophysics Data System (ADS)

    Goll, D.; Kronmüller, H.

    High-performance permanent magnets (pms) are based on compounds with outstanding intrinsic magnetic properties as well as on optimized microstructures and alloy compositions. The most powerful pm materials at present are RE-TM intermetallic alloys which derive their exceptional magnetic properties from the favourable combination of rare earth metals (RE=Nd, Pr, Sm) with transition metals (TM=Fe, Co), in particular magnets based on (Nd,Pr)2Fe14B and Sm2(Co,Cu,Fe,Zr)17. Their development during the last 20 years has involved a dramatic improvement in their performance by a factor of >15 compared with conventional ferrite pms therefore contributing positively to the ever-increasing demand for pms in many (including new) application fields, to the extent that RE-TM pms now account for nearly half of the worldwide market. This review article first gives a brief introduction to the basics of ferromagnetism to confer an insight into the variety of (permanent) magnets, their manufacture and application fields. We then examine the rather complex relationship between the microstructure and the magnetic properties for the two highest-performance and most promising pm materials mentioned. By using numerical micromagnetic simulations on the basis of the Finite Element technique the correlation can be quantitatively predicted, thus providing a powerful tool for the further development of optimized high-performance pms.

  14. Seeing is saving: the benefit of 3D imaging in gynecologic brachytherapy.

    PubMed

    Viswanathan, Akila N; Erickson, Beth A

    2015-07-01

    Despite a concerning decline in the use of brachytherapy over the past decade, no other therapy is able to deliver a very high dose of radiation into or near a tumor, with a rapid fall-off of dose to adjacent structures. Compared to traditional X-ray-based brachytherapy that relies on points, the use of CT and MR for 3D planning of gynecologic brachytherapy provides a much more accurate volume-based calculation of dose to an image-defined tumor and to the bladder, rectum, sigmoid, and other pelvic organs at risk (OAR) for radiation complications. The publication of standardized guidelines and an online contouring teaching atlas for performing 3D image-based brachytherapy has created a universal platform for communication and training. This has resulted in a uniform approach to using image-guided brachytherapy for treatment and an internationally accepted format for reporting clinical outcomes. Significant improvements in survival and reductions in toxicity have been reported with the addition of image guidance to increase dose to tumor and decrease dose to the critical OAR. Future improvements in individualizing patient treatments should include a more precise definition of the target. This will allow dose modulation based on the amount of residual disease visualized on images obtained at the time of brachytherapy.

  15. WE-E-BRD-01: HDR Brachytherapy I: Overview of Clinical Application and QA

    SciTech Connect

    Libby, B; Showalter, T

    2014-06-15

    With the increased usage of high dose rate (HDR) brachytherapy and the introduction of dedicated image guided brachytherapy suites, it is necessary to review the processes and procedures associated with safely delivering these treatments in the expedited time scales that dedicated treatment suites afford. The speakers will present the clinical aspects of switching from LDR to HDR treatments, including guidelines for patient selection, and the clinical outcomes comparing LDR to HDR. The speakers will also discuss the HDR treatment process itself, because the shortened clinical timeline involved with a streamlined scan/plan/treat workflow can introduce other issues. Safety and QA aspects involved with the streamlined process, including increased personnel required for parallel tasks, and possible interfering tasks causing delays in patient treatments will also be discussed. Learning Objectives: To understand the clinical aspects of HDR Brachytherapy, including common clinical indications, patient selection, and the evolving evidence in support of this therapeutic modality To review the current prominent clinical trials for HDR brachytherapy To interpret the established guidelines for HDR brachytherapy quality assurance for implementation into practical clinical settings. To introduce the basic requirements for image guided brachytherapy.

  16. Adherence to Vaginal Dilation Following High Dose Rate Brachytherapy for Endometrial Cancer

    SciTech Connect

    Friedman, Lois C.; Abdallah, Rita; Schluchter, Mark; Panneerselvam, Ashok; Kunos, Charles A.

    2011-07-01

    Purpose: We report demographic, clinical, and psychosocial factors associated with adherence to vaginal dilation and describe the sexual and marital or nonmarital dyadic functioning of women following high dose rate (HDR) brachytherapy for endometrial cancer. Methods and Materials: We retrospectively evaluated women aged 18 years or older in whom early-stage endometrial (IAgr3-IIB) cancers were treated by HDR intravaginal brachytherapy within the past 3.5 years. Women with or without a sexual partner were eligible. Patients completed questionnaires by mail or by telephone assessing demographic and clinical variables, adherence to vaginal dilation, dyadic satisfaction, sexual functioning, and health beliefs. Results: Seventy-eight of 89 (88%) eligible women with early-stage endometrial cancer treated with HDR brachytherapy completed questionnaires. Only 33% of patients were adherers, based on reporting having used a dilator more than two times per week in the first month following radiation. Nonadherers who reported a perceived change in vaginal dimension following radiation reported that their vaginas were subjectively smaller after brachytherapy (p = 0.013). Adherers reported more worry about their sex lives or lack thereof than nonadherers (p = 0.047). Patients reported considerable sexual dysfunction following completion of HDR brachytherapy. Conclusions: Adherence to recommendations for vaginal dilator use following HDR brachytherapy for endometrial cancer is poor. Interventions designed to educate women about dilator use benefit may increase adherence. Although sexual functioning was compromised, it is likely that this existed before having cancer for many women in our study.

  17. Perioperative Search for Circulating Tumor Cells in Patients Undergoing Prostate Brachytherapy for Clinically Nonmetastatic Prostate Cancer

    PubMed Central

    Tsumura, Hideyasu; Satoh, Takefumi; Ishiyama, Hiromichi; Tabata, Ken-ichi; Takenaka, Kouji; Sekiguchi, Akane; Nakamura, Masaki; Kitano, Masashi; Hayakawa, Kazushige; Iwamura, Masatsugu

    2017-01-01

    Despite the absence of local prostate cancer recurrence, some patients develop distant metastases after prostate brachytherapy. We evaluate whether prostate brachytherapy procedures have a potential risk for hematogenous spillage of prostate cancer cells. Fifty-nine patients who were undergoing high-dose-rate (HDR) or low-dose-rate (LDR) brachytherapy participated in this prospective study. Thirty patients with high-risk or locally advanced cancer were treated with HDR brachytherapy after neoadjuvant androgen deprivation therapy (ADT). Twenty-nine patients with clinically localized cancer were treated with LDR brachytherapy without neoadjuvant ADT. Samples of peripheral blood were drawn in the operating room before insertion of needles (preoperative) and again immediately after the surgical manipulation (intraoperative). Blood samples of 7.5 mL were analyzed for circulating tumor cells (CTCs) using the CellSearch System. While no preoperative samples showed CTCs (0%), they were detected in intraoperative samples in 7 of the 59 patients (11.8%; preoperative vs. intraoperative, p = 0.012). Positive CTC status did not correlate with perioperative variables, including prostate-specific antigen (PSA) at diagnosis, use of neoadjuvant ADT, type of brachytherapy, Gleason score, and biopsy positive core rate. We detected CTCs from samples immediately after the surgical manipulation. Further study is needed to evaluate whether those CTCs actually can survive and proliferate at distant sites. PMID:28085051

  18. Monte Carlo calculations and experimental measurements of dosimetric parameters of the IRA-{sup 103}Pd brachytherapy source

    SciTech Connect

    Sadeghi, Mahdi; Raisali, Gholamreza; Hosseini, S. Hamed; Shavar, Arzhang

    2008-04-15

    This article presents a brachytherapy source having {sup 103}Pd adsorbed onto a cylindrical silver rod that has been developed by the Agricultural, Medical, and Industrial Research School for permanent implant applications. Dosimetric characteristics (radial dose function, anisotropy function, and anisotropy factor) of this source were experimentally and theoretically determined in terms of the updated AAPM Task group 43 (TG-43U1) recommendations. Monte Carlo simulations were used to calculate the dose rate constant. Measurements were performed using TLD-GR200A circular chip dosimeters using standard methods employing thermoluminescent dosimeters in a Perspex phantom. Precision machined bores in the phantom located the dosimeters and the source in a reproducible fixed geometry, providing for transverse-axis and angular dose profiles over a range of distances from 0.5 to 5 cm. The Monte Carlo N-particle (MCNP) code, version 4C simulation techniques have been used to evaluate the dose-rate distributions around this model {sup 103}Pd source in water and Perspex phantoms. The Monte Carlo calculated dose rate constant of the IRA-{sup 103}Pd source in water was found to be 0.678 cGy h{sup -1} U{sup -1} with an approximate uncertainty of {+-}0.1%. The anisotropy function, F(r,{theta}), and the radial dose function, g(r), of the IRA-{sup 103}Pd source were also measured in a Perspex phantom and calculated in both Perspex and liquid water phantoms.

  19. Dosimetric comparison of four new design {sup 103}Pd brachytherapy sources: Optimal design using silver and copper rod cores

    SciTech Connect

    Hosseini, S. Hamed; Sadeghi, Mahdi; Ataeinia, Vahideh

    2009-07-15

    Four new brachytherapy sources, IRA1-{sup 103}Pd, IRA2-{sup 103}Pd, IRA3-{sup 103}Pd, and IRA4-{sup 103}Pd, have been developed at Agricultural, Medical, and Industrial Research School and are designed for permanent implant application. With the goal of determining an optimal design for a {sup 103}Pd source, this article compares the dosimetric properties of these sources with reference to the authors' earlier IRA-{sup 103}Pd source. The four new sources differ in end cap configuration and thickness and in the core material, silver or copper, that carries the adsorbed {sup 103}Pd. Dosimetric data derived from the authors' Monte Carlo simulation results are reported in accordance with the updated AAPM Task Group No. 43 report (TG-43U1). For each source, the authors obtained detailed results for the dose rate constant {Lambda}, the radial dose function g(r), the anisotropy function F(r,{theta}), and the anisotropy factor {phi}{sub an}(r). In this study, the optimal source IRA3-{sup 103}Pd provides the most isotropic dose distribution in water with the dose rate constant of 0.678({+-}0.1%) cGy h{sup -1} U{sup -1}. The IRA3-{sup 103}Pd design has a silver rod core combined with thin-wall, concave end caps. Finally, the authors compared the results for their optimal source with published results for those of other source manufacturers.

  20. Endobronchial brachytherapy in the treatment of malignant lung tumours.

    PubMed

    Escobar-Sacristán, J A; Granda-Orive, J I; Gutiérrez Jiménez, T; Delgado, J M; Rodero Baños, A; Saez Valls, R

    2004-09-01

    A prospective study was made to assess the short-term clinical and endoscopic response to high-dose-rate endobronchial brachytherapy (HDREB) in patients with malignant endobronchial tumours. From July 1995 to May 2000, 288 HDREB sessions were carried out on 81 patients. The mean patient age was 61.57 yrs (range 34-82); males were predominant (87.65%). Tumours were primary in 76 patients (93.82%) and metastatic in five patients (6.18%). The inclusion criteria were malignant endobronchial tumour and either palliative treatment for incurable disease or intent-to-cure treatment for residual malignancy on the bronchial resection surface after surgery or an inoperable tumour. The exclusion criteria were as follows: impediments to catheter placement, expected survival <2 months, Karnofsky index <60, or absence of informed consent. The clinical response of a symptom was categorised as complete (disappearance of the symptom), partial (less than complete) or absent. The endoscopic response was considered to be complete if lesions disappeared and biopsy findings remained negative 1 month after the last radiation session; partial if lesions improved to some extent, but the biopsy findings were positive; and absent if there was no change in relation to baseline. The technique consisted of delivering high-dose irradiation from an Ir192 source to a target volume using one or two endobronchial catheters inserted under optical or video bronchoscopic guidance. Four sessions were scheduled at weekly intervals and 500 cGy was applied per session over a length of 1-9 cm, measured 0.5-1 cm from the centre of the source. In total, 85% of the symptoms analysed (haemoptysis, cough, dyspnoea, expectoration, and stridor) disappeared with HDREB, which was categorised as a complete response. The endoscopic response was complete in 56.79% of patients, partial or less than complete in 40.74% and absent in 2.46%. One major complication occurred (bronchial fistula 1.2%), but no lethal haemoptysis

  1. Dosimetric equivalence of nonstandard HDR brachytherapy catheter patterns

    SciTech Connect

    Cunha, J. A. M.; Hsu, I-C.; Pouliot, J.

    2009-01-15

    Purpose: To determine whether alternative high dose rate prostate brachytherapy catheter patterns can result in similar or improved dose distributions while providing better access and reducing trauma. Materials and Methods: Standard prostate cancer high dose rate brachytherapy uses a regular grid of parallel needle positions to guide the catheter insertion. This geometry does not easily allow the physician to avoid piercing the critical structures near the penile bulb nor does it provide position flexibility in the case of pubic arch interference. This study used CT datasets with 3 mm slice spacing from ten previously treated patients and digitized new catheters following three hypothetical catheter patterns: conical, bi-conical, and fireworks. The conical patterns were used to accommodate a robotic delivery using a single entry point. The bi-conical and fireworks patterns were specifically designed to avoid the critical structures near the penile bulb. For each catheter distribution, a plan was optimized with the inverse planning algorithm, IPSA, and compared with the plan used for treatment. Irrelevant of catheter geometry, a plan must fulfill the RTOG-0321 dose criteria for target dose coverage (V{sub 100}{sup Prostate}>90%) and organ-at-risk dose sparing (V{sub 75}{sup Bladder}<1 cc, V{sub 75}{sup Rectum}<1 cc, V{sub 125}{sup Urethra}<<1 cc). Results: The three nonstandard catheter patterns used 16 nonparallel, straight divergent catheters, with entry points in the perineum. Thirty plans from ten patients with prostate sizes ranging from 26 to 89 cc were optimized. All nonstandard patterns fulfilled the RTOG criteria when the clinical plan did. In some cases, the dose distribution was improved by better sparing the organs-at-risk. Conclusion: Alternative catheter patterns can provide the physician with additional ways to treat patients previously considered unsuited for brachytherapy treatment (pubic arch interference) and facilitate robotic guidance of

  2. Critical Organ Preservation in Reirradiation Brachytherapy by Injectable Spacer

    SciTech Connect

    Kishi, Kazushi Sonomura, Tetsuo; Shirai, Shintaro; Sato, Morio; Tanaka, Kayo

    2009-10-01

    Purpose: This case series study evaluated the feasibility and effectiveness of an interstitial high-dose rate brachytherapy (HDR-BT) procedure combined with an at-risk organ-sparing procedure. Methods and Materials: Thirty patients who were scheduled for reirradiation treatment for recurrent cancer after receiving a median dose of 60 Gy (range, 44-70 Gy) in 2-Gy fractions of previous external beam treatment were enrolled. Thirteen patients had lesions in the head and neck, and other lesions were located in the axilla, skeleton, breast, pelvis, and abdominal wall. Chief complaints included local masses (for 25) and refractory pain (for 21). After high-dose rate brachytherapy applicator needle implantation, an optimal CT-based three-dimensional brachytherapy plan was created with a virtual at-risk organ shift from the target. According to the plan, hyaluronic acid gel was injected to maintain the shift during irradiation. The prescribed dose was the result of an individualized tradeoff between target dose and at-risk organ dose, to avoid serious complications. A single-fraction dose of 18.0 Gy (median, equivalent to 75.6 Gy at an {alpha}/{beta} value of 3; range, 16-20 Gy) was applied to the tumor. Results: The at-risk organ dose decreased from 9.1 {+-} 0.9 Gy to 4.4 {+-} 0.4 Gy (mean {+-} standard deviation, p < 0.01), and the normal tissue complication probability decreased from 60.8% {+-} 12.6% to 16.1% {+-} 19.8% (p < 0.01). The shift effect lasted at least 4 hours and disappeared gradually. Distinct tumor shrinkage in 20 of 21 eligible patients, including tumor disappearance in 6 patients, pain reduction in 18 of 21 eligible patients, and no unexpected late toxicity greater than grade 2 were observed during the 19.5-month observation period. Conclusions: This at-risk organ-sparing preservation procedure may provide a safe and efficient reirradiation treatment.

  3. New permanent magnets; manganese compounds.

    PubMed

    Coey, J M D

    2014-02-12

    The exponential growth of maximum energy product that prevailed in the 20th century has stalled, leaving a market dominated by two permanent magnet materials, Nd2Fe14B and Ba(Sr)Fe12O19, for which the maximum theoretical energy products differ by an order of magnitude (515 kJ m(-3) and 45 kJ m(-3), respectively). Rather than seeking to improve on optimized Nd-Fe-B, it is suggested that some research efforts should be devoted to developing appropriately priced alternatives with energy products in the range 100-300 kJ m(-3). The prospects for Mn-based hard magnetic materials are discussed, based on known Mn-based compounds with the tetragonal L10 or D022 structure or the hexagonal B81 structure.

  4. Is CO2 ice permanent?

    NASA Technical Reports Server (NTRS)

    Lindner, Bernhard Lee

    1992-01-01

    Carbon dioxide ice has been inferred to exist at the south pole in summertime, but Earth based measurements in 1969 of water vapor in the Martian atmosphere suggest that all CO2 ice sublined from the southern polar cap and exposed underlying water ice. This implies that the observed summertime CO2 ice is of recent origin. It appears possible to construct an energy balance model that maintains seasonal CO2 ice at the south pole year round and still reasonably simulates the polar cap regression and atmospheric pressure data. This implies that the CO2 ice observed in the summertime south polar cap could be seasonal in origin, and that minor changes in climate could cause CO2 ice to completely vanish, as would appear to have happened in 1969. However, further research remains before it is certain whether the CO2 ice observed in the summertime south polar cap is seasonal or is part of a permanent reservoir.

  5. Permanence of Stochastic Lotka-Volterra Systems

    NASA Astrophysics Data System (ADS)

    Liu, Meng; Fan, Meng

    2017-04-01

    This paper proposes a new definition of permanence for stochastic population models, which overcomes some limitations and deficiency of the existing ones. Then, we explore the permanence of two-dimensional stochastic Lotka-Volterra systems in a general setting, which models several different interactions between two species such as cooperation, competition, and predation. Sharp sufficient criteria are established with the help of the Lyapunov direct method and some new techniques. This study reveals that the stochastic noises play an essential role in the permanence and characterize the systems being permanent or not.

  6. HDR intraluminal brachytherapy for lung tumours--a case report.

    PubMed

    Wee, J T; Yang, E T; Lim, Y C

    1994-06-01

    The lung is a common site for cancer to occur, for both primary as well as metastases. The presence of such tumours can give rise to symptoms such as haemoptysis, cough, breathlessness and pneumonia. In most cases, treatment is strictly for palliation. We present a case report of a patient with an endobronchial metastasis from a primary hypernephroma which recurred following external beam radiotherapy. He was treated with a single fraction of intraluminal brachytherapy to a dose of 10Gy at 1 cm from the axis on a High Dose Rate Ir192 Remote Afterloading Machine. There were no adverse effects following treatment. On follow-up 7 months later, the patient did not have any further recurrence of breathlessness although his disease had progressed at other sites.

  7. Radiobiological evaluation of low dose-rate prostate brachytherapy implants

    NASA Astrophysics Data System (ADS)

    Knaup, Courtney James

    Low dose-rate brachytherapy is a radiation therapy treatment for men with prostate cancer. While this treatment is common, the use of isotopes with varying dosimetric characteristics means that the prescription level and normal organ tolerances vary. Additionally, factors such as prostate edema, seed loss and seed migration may alter the dose distribution within the prostate. The goal of this work is to develop a radiobiological response tool based on spatial dose information which may be used to aid in treatment planning, post-implant evaluation and determination of the effects of prostate edema and seed migration. Aim 1: Evaluation of post-implant prostate edema and its dosimetric and biological effects. Aim 2: Incorporation of biological response to simplify post-implant evaluation. Aim 3: Incorporation of biological response to simplify treatment plan comparison. Aim 4: Radiobiologically based comparison of single and dual-isotope implants. Aim 5: Determine the dosimetric and radiobiological effects of seed disappearance and migration.

  8. Neutron brachytherapy for the treatment of malignant neoplasia

    SciTech Connect

    Maruyama, Y.

    1988-12-01

    In the 1930's both neutrons and the cyclotron were discovered, developed and used almost immediately for neutron beam therapy. Cf-252 was discovered in 1950 but its potential for cancer therapy was not postulated until 1965. Early sporadic clinical trials were used to treat only a few patients. The recognition of its curative properties and usefulness for bulky localized and radioresistant cancer therapy was not made until recently. In 1985, the Lexington Workshop led to a sharing of independent experiences from the USA, Japan, and the USSR; early trial experiences were related to neutron beam results. Localized neutron therapy using brachytherapy methods was found effective against radioresistance and bulky tumors. However, it needed to be used properly and with full appreciation of clinical oncology and the role of photon adjuvant therapy.

  9. Apparatus and method for high dose rate brachytherapy radiation treatment

    DOEpatents

    Macey, Daniel J.; Majewski, Stanislaw; Weisenberger, Andrew G.; Smith, Mark Frederick; Kross, Brian James

    2005-01-25

    A method and apparatus for the in vivo location and tracking of a radioactive seed source during and after brachytherapy treatment. The method comprises obtaining multiple views of the seed source in a living organism using: 1) a single PSPMT detector that is exposed through a multiplicity of pinholes thereby obtaining a plurality of images from a single angle; 2) a single PSPMT detector that may obtain an image through a single pinhole or a plurality of pinholes from a plurality of angles through movement of the detector; or 3) a plurality of PSPMT detectors that obtain a plurality of views from different angles simultaneously or virtually simultaneously. The plurality of images obtained from these various techniques, through angular displacement of the various acquired images, provide the information required to generate the three dimensional images needed to define the location of the radioactive seed source within the body of the living organism.

  10. Dose verification of eye plaque brachytherapy using spectroscopic dosimetry.

    PubMed

    Jarema, T; Cutajar, D; Weaver, M; Petasecca, M; Lerch, M; Kejda, A; Rosenfeld, A

    2016-09-01

    Eye plaque brachytherapy has been developed and refined for the last 80 years, demonstrating effective results in the treatment of ocular malignancies. Current dosimetry techniques for eye plaque brachytherapy (such as TLD- and film-based techniques) are time consuming and cannot be used prior to treatment in a sterile environment. The measurement of the expected dose distribution within the eye, prior to insertion within the clinical setting, would be advantageous, as any errors in source loading will lead to an erroneous dose distribution and inferior treatment outcomes. This study investigated the use of spectroscopic dosimetry techniques for real-time quality assurance of I-125 based eye plaques, immediately prior to insertion. A silicon detector based probe, operating in spectroscopy mode was constructed, containing a small (1 mm(3)) silicon detector, mounted within a ceramic holder, all encapsulated within a rubber sheath to prevent water infiltration of the electronics. Preliminary tests of the prototype demonstrated that the depth dose distribution through the central axis of an I-125 based eye plaque may be determined from AAPM Task Group 43 recommendations to a deviation of 6 % at 3 mm depth, 7 % at 5 mm depth, 1 % at 10 mm depth and 13 % at 20 mm depth, with the deviations attributed to the construction of the probe. A new probe design aims to reduce these discrepancies, however the concept of spectroscopic dosimetry shows great promise for use in eye plaque quality assurance in the clinical setting.

  11. Monte Carlo dosimetry of a new 90Y brachytherapy source

    PubMed Central

    Junxiang, Wu; Shihu, You; Jing, Huang; Fengxiang, Long; Chengkai, Wang; Zhangwen, Wu; Qing, Hou

    2015-01-01

    Purpose In this study, we attempted to obtain full dosimetric data for a new 90Y brachytherapy source developed by the College of Chemistry (Sichuan University) for use in high-dose-rate after-loading systems. Material and methods The dosimetric data for this new source were used as required by the dose calculation formalisms proposed by the AAPM Task Group 60 and Task Group 149. The active core length of the new 90Y source was increased to 4.7 mm compared to the value of 2.5 mm for the old 90Sr/90Y source. The Monte Carlo simulation toolkit Geant4 was used to calculate these parameters. The source was located in a 30-cm-radius theoretical sphere water phantom. Results The dosimetric data included the reference absorbed dose rate, the radial dose function in the range of 1.0 to 8.0 mm in the longitudinal axis, and the anisotropy function with a θ in the range of 0° to 90° at 5° intervals and an r in the range of 1.0 to 8.0 mm in 0.2-mm intervals. The reference absorbed dose rate for the new 90Y source was determined to be equal to 1.6608 ± 0.0008 cGy s–1 mCi–1, compared to the values of 0.9063 ± 0.0005 cGy s–1 mCi–1 that were calculated for the old 90Sr/90Y source. A polynomial function was also obtained for the radial dose function by curve fitting. Conclusions Dosimetric data are provided for the new 90Y brachytherapy source. These data are meant to be used commercially in after-loading system. PMID:26622247

  12. GAMMA DOSE RATE NEAR A NEW (252)Cf BRACHYTHERAPY SOURCE

    SciTech Connect

    Fortune, Eugene C; Gauld, Ian C; Wang, C

    2011-01-01

    A new generation of medical grade (252)Cf sources was developed in 2002 at the Oak Ridge National Laboratory. The combination of small size and large activity of (252)Cf makes the new source suitable to be used with the conventional high-dose-rate remote afterloading system for interstitial brachytherapy. A recent in-water calibration experiment showed that the measured gamma dose rates near the new source are slightly greater than the neutron dose rates, contradicting the well established neutron-to-gamma dose ratio of approximately 2:1 at locations near a (252)Cf brachytherapy source. Specifically, the MCNP-predicted gamma dose rate is a factor of two lower than the measured gamma dose rate at the distance of I cm, and the differences between the two results gradually diminish at distances farther away from the source. To resolve this discrepancy, we updated the source gamma spectrum by including in the ORIGEN-S data library the experimentally measured (252)Cf prompt gamma spectrum as well as the true (252)Cf spontaneous fission yield data to explicitly model delayed gamma emissions from fission products. We also investigated the bremsstrahlung X-rays produced by the beta particles emitted from fission product decays. The results show that the discrepancy of gamma dose rates is mainly caused by the omission of the bremsstrahlung X-rays in the MCNP runs. By including the bremsstrahlung X-rays, the MCNP results show that the gamma dose rates near a new (252)Cf source agree well with the measured results and that the gamma dose rates are indeed greater than the neutron dose rates.

  13. Dosimetry of the 198Au Source used in Interstitial Brachytherapy

    SciTech Connect

    Dauffy, L; Braby, L; Berner, B

    2004-05-18

    The American Association of Physicists in Medicine Task Group 43 report, AAPM TG-43, provides an analytical model and a dosimetry protocol for brachytherapy dose calculations, as well as documentation and results for some sealed sources. The radionuclide {sup 198}Au (T{sub 1/2} = 2.70 days, E{gamma} = 412 keV) has been used in the form of seeds for brachytherapy treatments including brain, eye, and prostate tumors. However, the TG-43 report has no data for {sup 198}Au seeds, and none have previously been obtained. For that reason, and because of the conversion of most treatment planning systems to TG-43 based methods, both Monte Carlo calculations (MCNP 4C) and thermoluminescent dosimeters (TLDs) are used in this work to determine these data. The geometric variation in dose is measured using an array of TLDs in a solid water phantom, and the seed activity is determined using both a well ion chamber and a High Purity Germanium detector (HPGe). The results for air kerma strength, S{sub k}, per unit apparent activity, are 2.06 (MCNP) and 2.09 (measured) U mCi{sup -1}. The former is identical to what was published in 1991 in the AAPM Task Group 32 report. The dose rate constant results, {Lambda}, are 1.12 (MCNP) and 1.10 (measured), cGy h{sup -1} U{sup -1}. The radial dose function, g(r), anisotropy function, F(r,{theta}), and anisotropy factor, {psi}{sub an}(r), are given. The anisotropy constant values are 0.973 (MCNP) and 0.994 (measured) and are consistent with both source geometry and the emitted photon energy.

  14. Treatment Planning for MRI Assisted Brachytherapy of Gynecologic Malignancies Based on Total Dose Constraints

    SciTech Connect

    Lang, Stefan Kirisits, Christian; Dimopoulos, Johannes; Georg, Dietmar; Poetter, Richard

    2007-10-01

    Purpose: To develop a method for treatment planning and optimization of magnetic resonance imaging (MRI)-assisted gynecologic brachytherapy that includes biologically weighted total dose constraints. Methods and Materials: The applied algorithm is based on the linear-quadratic model and includes dose, dose rate, and fractionation of the whole radiotherapy setting, consisting of external beam therapy plus high-dose-rate (HDR), low-dose-rate (LDR) or pulsed-dose rate (PDR) brachytherapy. Biologically effective doses (BED) are converted to more familiar isoeffective (equivalent) doses in 2-Gy fractions. For individual treatment planning of each brachytherapy fraction, the algorithm calculates the physical dose per brachytherapy fraction that corresponds to a predefined isoeffective total dose constraint. Achieved target dose and sparing of organs at risk of already delivered brachytherapy fractions are incorporated. Results: Since implementation for use in clinical routine in 2001, MRI assisted treatment plans of 216 gynecologic patients (161 HDR, 55 PDR brachytherapy) were prospectively optimized taking into account isoeffective dose-volume histogram-based total dose constraints for high-risk clinical target volume (HR CTV) and organs at risk (bladder, rectum, sigmoid). The algorithm is implemented in a spreadsheet and the procedure is fast and efficient. An uncertainty analysis of the isoeffective total doses based on variations of tissue parameters shows that confidence intervals are larger for PDR compared with HDR brachytherapy. For common treatment schedules, overall uncertainties of high-risk clinical target volume and organs at risk are within 8 Gy, except for the bladder when using the PDR technique. Conclusion: The presented method to respect total dose constraints is reliable and efficient and an essential tool when aiming to increase local control and minimize side effects.

  15. A comparison study on various low energy sources in interstitial prostate brachytherapy

    PubMed Central

    Bakhshabadi, Mahdi; Ghorbani, Mahdi; Knaup, Courtney; Meigooni, Ali S.

    2016-01-01

    Purpose Low energy sources are routinely used in prostate brachytherapy. 125I is one of the most commonly used sources. Low energy 131Cs source was introduced recently as a brachytherapy source. The aim of this study is to compare dose distributions of 125I, 103Pd, and 131Cs sources in interstitial brachytherapy of prostate. Material and methods ProstaSeed 125I brachytherapy source was simulated using MCNPX Monte Carlo code. Additionally, two hypothetical sources of 103Pd and 131Cs were simulated with the same geometry as the ProstaSeed 125I source, while having their specific emitted gamma spectra. These brachytherapy sources were simulated with distribution of forty-eight seeds in a phantom including prostate. The prostate was considered as a sphere with radius of 1.5 cm. Absolute and relative dose rates were obtained in various distances from the source along the transverse and longitudinal axes inside and outside the tumor. Furthermore, isodose curves were plotted around the sources. Results Analyzing the initial dose profiles for various sources indicated that with the same time duration and air kerma strength, 131Cs delivers higher dose to tumor. However, relative dose rate inside the tumor is higher and outside the tumor is lower for the 103Pd source. Conclusions The higher initial absolute dose in cGy/(h.U) of 131Cs brachytherapy source is an advantage of this source over the others. The higher relative dose inside the tumor and lower relative dose outside the tumor for the 103Pd source are advantages of this later brachytherapy source. Based on the total dose the 125I source has advantage over the others due to its longer half-life. PMID:26985200

  16. Radiofrequency ablation versus 125I-seed brachytherapy for painful metastases involving the bone

    PubMed Central

    Jiao, Dechao; Wu, Gang; Ren, Jianzhuang; Han, Xinwei

    2016-01-01

    This retrospective study aimed to demonstrate and compare the safety and effectiveness of computed tomography-guided radiofrequency ablation (RFA) and 125I-seed brachytherapy for painful bone metastases after failure of external beam radiotherapy (EBRT). From June 2013 to October 2015, 79 patients with moderate-to-severe pain caused by metastatic bone lesions who underwent either RFA (n = 41) or 125I-seed brachytherapy (n = 38) were enrolled. Pain in patients was measured using the brief pain inventory (BPI) before treatment, 1 week after treatment, and 3 months after treatment. Response rates were assessed by measuring the changes in pain and incorporation of changes in the analgesic requirements. At baseline, 1 week, and 3 months, the mean worst pain scores of BPI were 7.8, 5.4, and 2.7, respectively, for the RFA group and 7.7, 6.1, and 2.8, respectively, for the brachytherapy group. At 1 week, the complete and partial response rates were 12% and 59%, respectively, in the RFA group compared with 3% and 45%, respectively, in the brachytherapy group. At 3 months, the complete and partial response rates were 23% and 58%, respectively, in the RFA group compared with 24% and 52% in the brachytherapy group (p = 0.95). The response rates in the RFA group were significantly higher than those in the brachytherapy group at 1 week (p = 0.32), but comparable at 3 weeks (p = 0.95). Both groups had low rates of complications and no treatment-related mortality. In conclusion, the short-term curative efficiency of RFA was better than that of brachytherapy, but the log-term efficiency of both treatments was equal. PMID:27636995

  17. GGEMS-Brachy: GPU GEant4-based Monte Carlo simulation for brachytherapy applications

    NASA Astrophysics Data System (ADS)

    Lemaréchal, Yannick; Bert, Julien; Falconnet, Claire; Després, Philippe; Valeri, Antoine; Schick, Ulrike; Pradier, Olivier; Garcia, Marie-Paule; Boussion, Nicolas; Visvikis, Dimitris

    2015-07-01

    In brachytherapy, plans are routinely calculated using the AAPM TG43 formalism which considers the patient as a simple water object. An accurate modeling of the physical processes considering patient heterogeneity using Monte Carlo simulation (MCS) methods is currently too time-consuming and computationally demanding to be routinely used. In this work we implemented and evaluated an accurate and fast MCS on Graphics Processing Units (GPU) for brachytherapy low dose rate (LDR) applications. A previously proposed Geant4 based MCS framework implemented on GPU (GGEMS) was extended to include a hybrid GPU navigator, allowing navigation within voxelized patient specific images and analytically modeled 125I seeds used in LDR brachytherapy. In addition, dose scoring based on track length estimator including uncertainty calculations was incorporated. The implemented GGEMS-brachy platform was validated using a comparison with Geant4 simulations and reference datasets. Finally, a comparative dosimetry study based on the current clinical standard (TG43) and the proposed platform was performed on twelve prostate cancer patients undergoing LDR brachytherapy. Considering patient 3D CT volumes of 400  × 250  × 65 voxels and an average of 58 implanted seeds, the mean patient dosimetry study run time for a 2% dose uncertainty was 9.35 s (≈500 ms 10-6 simulated particles) and 2.5 s when using one and four GPUs, respectively. The performance of the proposed GGEMS-brachy platform allows envisaging the use of Monte Carlo simulation based dosimetry studies in brachytherapy compatible with clinical practice. Although the proposed platform was evaluated for prostate cancer, it is equally applicable to other LDR brachytherapy clinical applications. Future extensions will allow its application in high dose rate brachytherapy applications.

  18. GGEMS-Brachy: GPU GEant4-based Monte Carlo simulation for brachytherapy applications.

    PubMed

    Lemaréchal, Yannick; Bert, Julien; Falconnet, Claire; Després, Philippe; Valeri, Antoine; Schick, Ulrike; Pradier, Olivier; Garcia, Marie-Paule; Boussion, Nicolas; Visvikis, Dimitris

    2015-07-07

    In brachytherapy, plans are routinely calculated using the AAPM TG43 formalism which considers the patient as a simple water object. An accurate modeling of the physical processes considering patient heterogeneity using Monte Carlo simulation (MCS) methods is currently too time-consuming and computationally demanding to be routinely used. In this work we implemented and evaluated an accurate and fast MCS on Graphics Processing Units (GPU) for brachytherapy low dose rate (LDR) applications. A previously proposed Geant4 based MCS framework implemented on GPU (GGEMS) was extended to include a hybrid GPU navigator, allowing navigation within voxelized patient specific images and analytically modeled (125)I seeds used in LDR brachytherapy. In addition, dose scoring based on track length estimator including uncertainty calculations was incorporated. The implemented GGEMS-brachy platform was validated using a comparison with Geant4 simulations and reference datasets. Finally, a comparative dosimetry study based on the current clinical standard (TG43) and the proposed platform was performed on twelve prostate cancer patients undergoing LDR brachytherapy. Considering patient 3D CT volumes of 400  × 250  × 65 voxels and an average of 58 implanted seeds, the mean patient dosimetry study run time for a 2% dose uncertainty was 9.35 s (≈500 ms 10(-6) simulated particles) and 2.5 s when using one and four GPUs, respectively. The performance of the proposed GGEMS-brachy platform allows envisaging the use of Monte Carlo simulation based dosimetry studies in brachytherapy compatible with clinical practice. Although the proposed platform was evaluated for prostate cancer, it is equally applicable to other LDR brachytherapy clinical applications. Future extensions will allow its application in high dose rate brachytherapy applications.

  19. 10 CFR 35.2067 - Records of leaks tests and inventory of sealed sources and brachytherapy sources.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 1 2014-01-01 2014-01-01 false Records of leaks tests and inventory of sealed sources and brachytherapy sources. 35.2067 Section 35.2067 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Records § 35.2067 Records of leaks tests and inventory of sealed sources and brachytherapy...

  20. 10 CFR 35.2067 - Records of leaks tests and inventory of sealed sources and brachytherapy sources.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 1 2012-01-01 2012-01-01 false Records of leaks tests and inventory of sealed sources and brachytherapy sources. 35.2067 Section 35.2067 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Records § 35.2067 Records of leaks tests and inventory of sealed sources and brachytherapy...

  1. 22 CFR 401.3 - Permanent offices.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Relations INTERNATIONAL JOINT COMMISSION, UNITED STATES AND CANADA RULES OF PROCEDURE General § 401.3 Permanent offices. The permanent offices of the Commission shall be at Washington, in the District of... of the Commission shall have full charge and control of said offices, respectively....

  2. 22 CFR 401.3 - Permanent offices.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Relations INTERNATIONAL JOINT COMMISSION, UNITED STATES AND CANADA RULES OF PROCEDURE General § 401.3 Permanent offices. The permanent offices of the Commission shall be at Washington, in the District of... of the Commission shall have full charge and control of said offices, respectively....

  3. 22 CFR 401.3 - Permanent offices.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... Relations INTERNATIONAL JOINT COMMISSION, UNITED STATES AND CANADA RULES OF PROCEDURE General § 401.3 Permanent offices. The permanent offices of the Commission shall be at Washington, in the District of... of the Commission shall have full charge and control of said offices, respectively....

  4. 22 CFR 401.3 - Permanent offices.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... Relations INTERNATIONAL JOINT COMMISSION, UNITED STATES AND CANADA RULES OF PROCEDURE General § 401.3 Permanent offices. The permanent offices of the Commission shall be at Washington, in the District of... of the Commission shall have full charge and control of said offices, respectively....

  5. 22 CFR 401.3 - Permanent offices.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... Relations INTERNATIONAL JOINT COMMISSION, UNITED STATES AND CANADA RULES OF PROCEDURE General § 401.3 Permanent offices. The permanent offices of the Commission shall be at Washington, in the District of... of the Commission shall have full charge and control of said offices, respectively....

  6. First permanent molars with molar incisor hypomineralisation.

    PubMed

    Fitzpatrick, Laura; O'Connell, Anne

    2007-01-01

    Molar incisor hypomineralisation (MIH) is a common enamel defect presenting in the first permanent molars (FPM) and permanent incisors. This article presents the clinical findings and management considerations for the FPM with MIH to the general practitioner. The various treatment options are described with emphasis placed on early diagnosis as the most important prognostic factor.

  7. PREFORMED METAL CROWNS FOR THE PERMANENT DENTITION.

    PubMed

    Millar, Lynsey M; Cairns, Alison M; Fowler, Lauren

    2015-11-01

    Preformed metal crowns have a range of uses in paediatric dentistry in both the primary and permanent dentition. This article provides an overview of their use in permanent teeth, including teeth that have been affected by molar incisor hypomineralisation, caries, developmental defects and tooth surface loss. The indications for use are described, along with the clinical technique for placement

  8. Finite element modeling of permanent magnet devices

    NASA Astrophysics Data System (ADS)

    Brauer, J. R.; Larkin, L. A.; Overbye, V. D.

    1984-03-01

    New techniques are presented for finite element modeling of permanent magnets in magnetic devices such as motors and generators. These techniques extend a previous sheet-current permanent magnet model that applies only for straight line B-H loops and rectangular-shaped magnets. Here Maxwell's equations are used to derive the model of a permanent magnet having a general curved B-H loop and any geometric shape. The model enables a nonlinear magnetic finite element program to use Newton-Raphson iteration to solve for saturable magnetic fields in a wide variety of devices containing permanent magnets and steels. The techniques are applied to a brushless dc motor with irregular-shaped permanent magnets. The calculated motor torque agrees well with measured torque.

  9. Permanent magnet multipole with adjustable strength

    DOEpatents

    Halbach, Klaus

    1985-01-01

    Two or more magnetically soft pole pieces are symmetrically positioned along a longitudinal axis to provide a magnetic field within a space defined by the pole pieces. Two or more permanent magnets are mounted to an external magnetically-soft cylindrical sleeve which rotates to bring the permanent magnets into closer coupling with the pole pieces and thereby adjustably control the field strength of the magnetic field produced in the space defined by the pole pieces. The permanent magnets are preferably formed of rare earth cobalt (REC) material which has a high remanent magnetic field and a strong coercive force. The pole pieces and the permanent magnets have corresponding cylindrical surfaces which are positionable with respect to each other to vary the coupling therebetween. Auxiliary permanent magnets are provided between the pole pieces to provide additional magnetic flux to the magnetic field without saturating the pole pieces.

  10. Permanent-magnet multipole with adjustable strength

    DOEpatents

    Halbach, K.

    1982-09-20

    Two or more magnetically soft pole pieces are symmetrically positioned along a longitudinal axis to provide a magnetic field within a space defined by the pole pieces. Two or more permanent magnets are mounted to an external magnetically-soft cylindrical sleeve which rotates to bring the permanent magnets into closer coupling with the pole pieces and thereby adjustably control the field strength of the magnetic field produced in the space defined by the pole pieces. The permanent magnets are preferably formed of rare earth cobalt (REC) material which has a high remanent magnetic field and a strong coercive force. The pole pieces and the permanent magnets have corresponding cylindrical surfaces which are positionable with respect to each other to vary the coupling there between. Auxiliary permanent magnets are provided between the pole pieces to provide additional magnetic flux to the magnetic field without saturating the pole pieces.

  11. Gating of Permanent Molds for ALuminum Casting

    SciTech Connect

    David Schwam; John F. Wallace; Tom Engle; Qingming Chang

    2004-03-30

    This report summarizes a two-year project, DE-FC07-01ID13983 that concerns the gating of aluminum castings in permanent molds. The main goal of the project is to improve the quality of aluminum castings produced in permanent molds. The approach taken was determine how the vertical type gating systems used for permanent mold castings can be designed to fill the mold cavity with a minimum of damage to the quality of the resulting casting. It is evident that somewhat different systems are preferred for different shapes and sizes of aluminum castings. The main problems caused by improper gating are entrained aluminum oxide films and entrapped gas. The project highlights the characteristic features of gating systems used in permanent mold aluminum foundries and recommends gating procedures designed to avoid common defects. The study also provides direct evidence on the filling pattern and heat flow behavior in permanent mold castings.

  12. Leadership in a (permanent) crisis.

    PubMed

    Heifetz, Ronald; Grashow, Alexander; Linsky, Marty

    2009-01-01

    The current economic crisis is not just another rough spell. Today's mix of urgency, high stakes, and uncertainty will continue even after the recession ends. The immediate crisis--which we will get through with policy makers' expert technical adjustments--sets the stage for a sustained, or even permanent, crisis, a relentless series of challenges no one has encountered before. Instead of hunkering down and relying on their familiar expertise to deal with the sustained crisis, people in positions of authority--whether they are CEOs or managers heading up a company initiative--must practice what the authors call adaptive leadership. They must, of course, tackle the underlying causes of the crisis, but they must also simultaneously make the changes that will allow their organizations to thrive in turbulent environments. Adaptive leadership is an improvisational and experimental art, requiring some new practices. Like Julie Gilbert, who overcame internal resistance to reorient Best Buy toward female purchasers, adaptive leaders get things done to meet today's challenges and then modify those things to thrive in tomorrow's world. They also embrace disequilibrium, using turbulence as an opportunity to build crucial new capacities, as Paul Levy did to rescue Beth Israel Deaconess Medical Center from a profound financial crisis. Finally, adaptive leaders, such as Egon Zehnder, the founder of an executive search firm, draw out the leadership skills that reside deep in the organization, recognizing the interdependence of all employees and mobilizing everyone to generate solutions.

  13. Iodine-125-labeled lipoprotein lipase as a tool to detect and study spontaneous lipolysis in bovine milk

    SciTech Connect

    Sundheim, G.; Bengtsson-Olivecrona, G.

    1986-07-01

    The distribution of lipoprotein lipase among cream, casein, and milk serum can be evaluated by addition of a trace amount of /sup 125/I-labeled lipoprotein lipase to milk. Radioactive lipase was distributed in parallel to endogenous lipase under several conditions. In some milk samples, binding of lipase to cream increased when the milk was cooled. Correlation was good between bound labeled lipase and degree of cold-induced lipolysis in corresponding milk samples. Binding of lipase to cream or to casein was not saturable by addition of two-to threefold more lipase than is normally present in milk. In milk with a relatively high fraction of lipase bound to cream, a correspondingly lower fraction was associated with casein, whereas the fraction of lipase in milk serum was similar in all milk samples. Cold-induced binding of lipoprotein lipase to cream was not fully reversed when the milk was warmed again. Heparin released lipase from casein and increased the amount of lipase bound to cream after cooling.

  14. Uveal Melanoma Treated With Iodine-125 Episcleral Plaque: An Analysis of Dose on Disease Control and Visual Outcomes

    SciTech Connect

    Perez, Bradford A.; Mettu, Pradeep; Vajzovic, Lejla; Rivera, Douglas; Alkaissi, Ali; Steffey, Beverly A.; Cai, Jing; Stinnett, Sandra; Dutton, Jonathan J.; Buckley, Edward G.; Halperin, Edward; Marks, Lawrence B.; Mruthyunjaya, Prithvi; Kirsch, David G.

    2014-05-01

    Purpose: To investigate, in the treatment of uveal melanomas, how tumor control, radiation toxicity, and visual outcomes are affected by the radiation dose at the tumor apex. Methods and Materials: A retrospective review was performed to evaluate patients treated for uveal melanoma with {sup 125}I plaques between 1988 and 2010. Radiation dose is reported as dose to tumor apex and dose to 5 mm. Primary endpoints included time to local failure, distant failure, and death. Secondary endpoints included eye preservation, visual acuity, and radiation-related complications. Univariate and multivariate analyses were performed to determine associations between radiation dose and the endpoint variables. Results: One hundred ninety patients with sufficient data to evaluate the endpoints were included. The 5-year local control rate was 91%. The 5-year distant metastases rate was 10%. The 5-year overall survival rate was 84%. There were no differences in outcome (local control, distant metastases, overall survival) when dose was stratified by apex dose quartile (<69 Gy, 69-81 Gy, 81-89 Gy, >89 Gy). However, increasing apex dose and dose to 5-mm depth were correlated with greater visual acuity loss (P=.02, P=.0006), worse final visual acuity (P=.02, P<.0001), and radiation complications (P<.0001, P=.0009). In addition, enucleation rates were worse with increasing quartiles of dose to 5 mm (P=.0001). Conclusions: Doses at least as low as 69 Gy prescribed to the tumor apex achieve rates of local control, distant metastasis–free survival, and overall survival that are similar to radiation doses of 85 Gy to the tumor apex, but with improved visual outcomes.

  15. Method for the simultaneous preparation of radon-211, xenon-125, xenon-123, astatine-211, iodine-125 and iodine-123

    SciTech Connect

    Mirzadeh, S.; Lambrecht, R.M.

    1987-05-12

    A method is described for simultaneously preparing a mixture of about equal amounts of /sup 211/Rn and /sup 125/Xe, and a second mixture of about equal amounts of /sup 211/At and /sup 123/I with a proton-irradiation procedure followed by a one-step chemical procedure. The method comprises: irradiating a body of material selected from the group consisting of /sup 232/Th and /sup 238/U for about 15 hours with protons that have been accelerated to at least 2 GeV; promptly dissolving the irradiated body of material in a vessel containing a mixture of hydrochloric acid, nitric acid and hydrofluoric acid; and forcing a stream of helium (He) carrier gas into the vessel at a predetermined flow rate to entrain radionuclides of gaseous /sup 210/Rn, /sup 211/Rn, /sup 123/Xe and /sup 125/Xe and trace amounts of radiohalogens and remove them from the vessel.

  16. Iodine 125-lysergic acid diethylamide binds to a novel serotonergic site on rat choroid plexus epithelial cells

    SciTech Connect

    Yagaloff, K.A.; Hartig, P.R.

    1985-12-01

    /sup 125/I-Lysergic acid diethylamide (/sup 125/I-LSD) binds with high affinity to serotonergic sites on rat choroid plexus. These sites were localized to choroid plexus epithelial cells by use of a novel high resolution stripping film technique for light microscopic autoradiography. In membrane preparations from rat choroid plexus, the serotonergic site density was 3100 fmol/mg of protein, which is 10-fold higher than the density of any other serotonergic site in brain homogenates. The choroid plexus site exhibits a novel pharmacology that does not match the properties of 5-hydroxytryptamine-1a (5-HT1a), 5-HT1b, or 5-HT2 serotonergic sites. /sup 125/I-LSD binding to the choroid plexus site is potently inhibited by mianserin, serotonin, and (+)-LSD. Other serotonergic, dopaminergic, and adrenergic agonists and antagonists exhibit moderate to weak affinities for this site. The rat choroid plexus /sup 125/I-LSD binding site appears to represent a new type of serotonergic site which is located on non-neuronal cells in this tissue.

  17. Method for the simultaneous preparation of radon-211, xenon-125, xenon-123, astatine-211, iodine-125 and iodine-123

    DOEpatents

    Mirzadeh, S.; Lambrecht, R.M.

    1985-07-01

    The invention relates to a practical method for commercially producing radiopharmaceutical activities and, more particularly, relates to a method for the preparation of about equal amount of Radon-211 (/sup 211/Rn) and Xenon-125 (/sup 125/Xe) including a one-step chemical procedure following an irradiation procedure in which a selected target of Thorium (/sup 232/Th) or Uranium (/sup 238/U) is irradiated. The disclosed method is also effective for the preparation in a one-step chemical procedure of substantially equal amounts of high purity /sup 123/I and /sup 211/At. In one preferred arrangement of the invention almost equal quantities of /sup 211/Rn and /sup 125/Xe are prepared using a onestep chemical procedure in which a suitably irradiated fertile target material, such as thorium-232 or uranium-238, is treated to extract those radionuclides from it. In the same one-step chemical procedure about equal quantities of /sup 211/At and /sup 123/I are prepared and stored for subsequent use. In a modified arrangement of the method of the invention, it is practiced to separate and store about equal amounts of only /sup 211/Rn and /sup 125/Xe, while preventing the extraction or storage of the radionuclides /sup 211/At and /sup 123/I.

  18. Synthesis of iodine-125 labeled (+/-)-15-(4-azidobenzyl)carazolol: a potent beta-adrenergic photoaffinity probe

    SciTech Connect

    Heald, S.L.; Jeffs, P.W.; Lavin, T.N.; Nambi, P.; Lefkowitz, R.J.; Caron, M.G.

    1983-06-01

    (+/-)-15-(4-Azidobenzyl)carazolol (2), a potent beta-adrenergic photoaffinity ligand has been radioiodinated to theoretical specific activity (2175 Ci/mmol) and shown to label covalently beta-adrenergic receptor peptides in avian and amphibian erythrocyte membrane preparations. The radioiodinated analogues of the desired compound (2) were optimally prepared by two synthetic steps from (+/-)-15-(4-aminobenzyl)carazolol (8). The latter was iodinated with carrier-free Na/sup 125/I and chloramine T to yield two major isotopomers (the monoiodinated derivatives 9 and 10), which were separated by thin-layer chromatography and converted via diazonium salt formation to their respective 4-azides, 12 and 6. These azides can be used interchangeably in ligand binding or photoaffinity labeling experiments. Compound 8 was obtained by catalytic reduction of the nitro derivative (7), which was arrived at by direct reaction of 1,1-dimethyl-2-(4-nitrophenyl)ethylamine (3) with 4-(2,3-epoxypropoxy)carbazole (5). Of the desired isomers, (+/-)-15-(4-azido-3-iodobenzyl)carazolol (6) could be synthesized from 1,1-dimethyl-2-(4-azido-3-iodophenyl)ethylamine (4) by direct reaction with 5. This and the preceding sequence of reactions were carried out by using nonradioactive materials, and separation and purification of products were accomplished by high-performance liquid chromatography. The compounds described have been shown to be potent beta-adrenergic antagonistsec The photoactive azide derivatives of these compounds (6 and 12) have been shown to covalently incorporate into the beta-adrenergic receptor binding subunit of frog and turkey erythrocyte membrane preparations. Incorporation of the ligands into these polypeptides can be blocked specifically by both beta-adrenergic agonists and antagonists.

  19. Radioiodination of 3-quinuclidinyl benzilate using a no-carrier-added concentration of iodine-125/sodium-iodine

    SciTech Connect

    Lee, K.S.

    1986-01-01

    3-Quinuclidinyl benzilate (QNB) is a potent muscarinic antagonist that binds to muscarinic acetylcholine receptors. Iodination of QNB is difficult because it contains rings that are deactivated, while phenol rings are activated. The purpose of this research is to develop an appropriate method for the iodination of QNB at no-carrier-added concentrations of /sup 125/I/NaI. Phenol was chose as the test compound for direct iodination by adding chloramine T and nonradioactive sodium iodide to the phenol in a phosphate buffer and methanol system. A simple method to radioiodinate QNB at several concentrations was developed in situ in the presence of QNB, thallic trifluoroacetate /sup 125/I/NaI, /sup 127/I/NaI, and aluminium chloride. Using milligram amounts of QNB (7.12 x 10/sup -6/ moles), three reaction steps were involved: QNB was reacted with thallic trifluoroacetate at 60/sup 0/C for 24 hours, then radioactive /sup 125/I/NaI and aluminium chloride were added to the reaction mixture and the reaction continued at 70/sup 0/C for 3 hours, and then nonradioactive /sup 127/I/NaI was added to this mixture and continued at 70/sup 0/C for another hour. Using microgram amounts of QNB (1.06 x 10/sup 7/ moles) in the no-carrier-added radioiodination, the optimal yield of (/sup 125/I)m-IQNB was obtained when the same mole ratio of QNB:aluminum chloride:thallic trifluoroacetate was used and the radioactive /sup 125/I/NaI reaction was allowed to continue at 70/sup 0/C for 24 hours while all other variables were held constant. The m-IQNB from the crude reaction mixture was purified by high performance liquid chromatography (HPLC). Thin-layer chromatography showed one peak from the HPLC fraction numbers 28-31.

  20. A comparison of the expected costs of high dose rate brachytherapy using 252Cf versus 192Ir.

    PubMed

    Rivard, Mark J; Kirk, Bernadette L; Stapleford, Liza J; Wazer, David E

    2004-12-01

    A cost analysis to compare high dose rate (HDR) brachytherapy using either californium-252 (252Cf) or 192Ir was performed to determine the prospects of widespread clinical implementation of HDR 252Cf. Interest in the neutron-emitting 252Cf radioisotope as a radiotherapy nuclide has undergone a resurgence given recent efforts to fabricate HDR remotely afterloaded sources, and other efforts to create a miniature source for improved accessibility to a variety of anatomic sites. Therefore, HDR 252Cf brachytherapy may prove to be a potential rival to the use of HDR 192Ir remotely afterloaded brachytherapy--the current standard-of-care treatment modality using HDR brachytherapy. Considering the possible improvements in clinical efficacy using HDR 252Cf brachytherapy and the enormous costs of other high-LET radiation sources, the cost differences between 252Cf and 192Ir may be well-justified.

  1. Long-Term Efficacy and Toxicity of Low-Dose-Rate {sup 125}I Prostate Brachytherapy as Monotherapy in Low-, Intermediate-, and High-Risk Prostate Cancer

    SciTech Connect

    Kittel, Jeffrey A.; Reddy, Chandana A.; Smith, Kristin L.; Stephans, Kevin L.; Tendulkar, Rahul D.; Ulchaker, James; Angermeier, Kenneth; Campbell, Steven; Stephenson, Andrew; Klein, Eric A.; Wilkinson, D. Allan; Ciezki, Jay P.

    2015-07-15

    Purpose/Objectives: To report long-term efficacy and toxicity for a single-institution cohort of patients treated with low-dose-rate prostate brachytherapy permanent implant (PI) monotherapy. Methods and Materials: From 1996 to 2007, 1989 patients with low-risk (61.3%), intermediate-risk (29.8%), high-intermediate-risk (4.5%), and high-risk prostate cancer (4.4%) were treated with PI and followed up prospectively in a registry. All patients were treated with {sup 125}I monotherapy to 144 Gy. Late toxicity was coded retrospectively according to a modified Common Terminology Criteria for Adverse Events 4.0 scale. The rates of biochemical relapse-free survival (bRFS), distant metastasis-free survival (DMFS), overall survival (OS), and prostate cancer–specific mortality (PCSM) were calculated. We identified factors associated with late grade ≥3 genitourinary (GU) and gastrointestinal (GI) toxicity, bRFS, DMFS, OS, PCSM, and incontinence. Results: The median age of the patients was 67 years, and the median overall and prostate-specific antigen follow-up times were 6.8 years and 5.8 years, respectively. The overall 5-year rates for bRFS, DMFS, OS, and PCSM were 91.9%, 97.8%, 93.7%, and 0.71%, respectively. The 10-year rates were 81.5%, 91.5%, 76.1%, and 2.5%, respectively. The overall rates of late grade ≥3 GU and GI toxicity were 7.6% and 0.8%, respectively. On multivariable analysis, age and prostate length were significantly associated with increased risk of late grade ≥3 GU toxicity. The risk of incontinence was highly correlated with both pre-PI and post-PI transurethral resection of the prostate. Conclusions: Prostate brachytherapy as monotherapy is an effective treatment for low-risk and low-intermediate-risk prostate cancer and appears promising as a treatment for high-intermediate-risk and high-risk prostate cancer. Significant long-term toxicities are rare when brachytherapy is performed as monotherapy.

  2. Prescribing, recording, and reporting in endovascular brachytherapy. Quality assurance, equipment, personnel and education.

    PubMed

    Pötter, R; Van Limbergen, E; Dries, W; Popowski, Y; Coen, V; Fellner, C; Georg, D; Kirisits, C; Levendag, P; Marijnissen, H; Marsiglia, H; Mazeron, J J; Pokrajac, B; Scalliet, P; Tamburini, V

    2001-06-01

    Endovascular brachytherapy is a new, rapidly growing field of interest in radiotherapy for the prevention of neointimal hyperplasia after angioplasty in both coronary and peripheral arteries. Many physics aspects of these treatments have already been addressed in the report of the American Association of Physicists in Medicine task group on 'Intravascular brachytherapy', but up to now there are no generally accepted recommendations for recording and reporting radiation doses and volumes. The terminology to be used by all individuals involved in such treatments (radiation oncologists, physicists, and interventionalists) is not clearly defined. The Endovascular Groupe Européen de Curiethérapie/European Society for Therapeutic Radiology and Oncology Working Group in this document presents recommendations for a common language for general use in endovascular brachytherapy. This proposal addresses general terms and concepts for target and dose specification as well as detailed recommendations for dose prescription, recording and reporting in endovascular brachytherapy for both peripheral and coronary arteries. Additionally, quality assurance and radiation safety aspects are briefly addressed, as are aspects related to equipment, personnel, and training and education related to endovascular brachytherapy.

  3. Permanency and the Foster Care System.

    PubMed

    Lockwood, Katie K; Friedman, Susan; Christian, Cindy W

    2015-10-01

    Each year over 20,000 youth age out of the child welfare system without reaching a permanent placement in a family. Certain children, such as those spending extended time in foster care, with a diagnosed disability, or adolescents, are at the highest risk for aging out. As young adults, this population is at and increased risk of incarceration; food, housing, and income insecurity; unemployment; educational deficits; receipt of public assistance; and mental health disorders. We reviewed the literature on foster care legislation, permanency, outcomes, and interventions. The outcomes of children who age out of the child welfare system are poor. Interventions to increase permanency include training programs for youth and foster parents, age extension for foster care and insurance coverage, an adoption tax credit, and specialized services and programs that support youth preparing for their transition to adulthood. Future ideas include expanding mentoring, educational support, mental health services, and post-permanency services to foster stability in foster care placements and encourage permanency planning. Children in the child welfare system are at a high risk for physical, mental, and emotional health problems that can lead to placement instability and create barriers to achieving permanency. Failure to reach the permanency of a family leads to poor outcomes, which have negative effects on the individual and society. Supporting youth in foster care throughout transitions may mediate the negative outcomes that have historically followed placement in out-of-home care.

  4. Magnetic resonance imaging-guided brachytherapy for cervical cancer: initiating a program

    PubMed Central

    Prisciandaro, Joann I.; Soliman, Abraam; Ravi, Ananth; Song, William Y.

    2015-01-01

    Over the past decade, the application of magnetic resonance imaging (MRI) has increased, and there is growing evidence to suggest that improvements in accuracy of target delineation in MRI-guided brachytherapy may improve clinical outcomes in cervical cancer. To implement a high quality image guided brachytherapy program, a multidisciplinary team is required with appropriate expertise as well as an adequate patient load to ensure a sustainable program. It is imperative to know that the most important source of uncertainty in the treatment process is related to target delineation and therefore, the necessity of training and expertise as well as quality assurance should be emphasized. A short review of concepts and techniques that have been developed for implementation and/or improvement of workflow of a MRI-guided brachytherapy program are provided in this document, so that institutions can use and optimize some of them based on their resources to minimize their procedure times. PMID:26622249

  5. AAPM Task Group 128: Quality assurance tests for prostate brachytherapy ultrasound systems

    SciTech Connect

    Pfeiffer, Douglas; Sutlief, Steven; Feng Wenzheng; Pierce, Heather M.; Kofler, Jim

    2008-12-15

    While ultrasound guided prostate brachytherapy has gained wide acceptance as a primary treatment tool for prostate cancer, quality assurance of the ultrasound guidance system has received very little attention. Task Group 128 of the American Association of Physicists in Medicine was created to address quality assurance requirements specific to transrectal ultrasound used for guidance of prostate brachytherapy. Accurate imaging guidance and dosimetry calculation depend upon the quality and accuracy of the ultrasound image. Therefore, a robust quality assurance program for the ultrasound system is essential. A brief review of prostate brachytherapy and ultrasound physics is provided, followed by a recommendation for elements to be included in a comprehensive test phantom. Specific test recommendations are presented, covering grayscale visibility, depth of penetration, axial and lateral resolution, distance measurement, area measurement, volume measurement, needle template/electronic grid alignment, and geometric consistency with the treatment planning computer.

  6. Simulation of dose distribution for iridium-192 brachytherapy source type-H01 using MCNPX

    SciTech Connect

    Purwaningsih, Anik

    2014-09-30

    Dosimetric data for a brachytherapy source should be known before it used for clinical treatment. Iridium-192 source type H01 was manufactured by PRR-BATAN aimed to brachytherapy is not yet known its dosimetric data. Radial dose function and anisotropic dose distribution are some primary keys in brachytherapy source. Dose distribution for Iridium-192 source type H01 was obtained from the dose calculation formalism recommended in the AAPM TG-43U1 report using MCNPX 2.6.0 Monte Carlo simulation code. To know the effect of cavity on Iridium-192 type H01 caused by manufacturing process, also calculated on Iridium-192 type H01 if without cavity. The result of calculation of radial dose function and anisotropic dose distribution for Iridium-192 source type H01 were compared with another model of Iridium-192 source.

  7. Methodology for characterizing seeds under development for brachytherapy by means of radiochromic and photographic films.

    PubMed

    Meira-Belo, L C; Rodrigues, E J T; Grynberg, S E

    2013-04-01

    The development of new medical devices possess a number of challenges, including designing, constructing, and assaying prototypes. In the case of new brachytherapy seeds, this is also true. In this paper, a methodology for rapid dosimetric characterization of (125)I brachytherapy seeds during the early stages of their development is introduced. The characterization methodology is based on the joint use of radiochromic and personal monitoring photographic films in order to determine the planar anisotropy due to the radiation field produced by the seed under development, by means of isodose curves. To evaluate and validate the process, isodose curves were obtained with both types of films after irradiation with a commercial (125)I brachytherapy seed.

  8. Simulation of dose distribution for iridium-192 brachytherapy source type-H01 using MCNPX

    NASA Astrophysics Data System (ADS)

    Purwaningsih, Anik

    2014-09-01

    Dosimetric data for a brachytherapy source should be known before it used for clinical treatment. Iridium-192 source type H01 was manufactured by PRR-BATAN aimed to brachytherapy is not yet known its dosimetric data. Radial dose function and anisotropic dose distribution are some primary keys in brachytherapy source. Dose distribution for Iridium-192 source type H01 was obtained from the dose calculation formalism recommended in the AAPM TG-43U1 report using MCNPX 2.6.0 Monte Carlo simulation code. To know the effect of cavity on Iridium-192 type H01 caused by manufacturing process, also calculated on Iridium-192 type H01 if without cavity. The result of calculation of radial dose function and anisotropic dose distribution for Iridium-192 source type H01 were compared with another model of Iridium-192 source.

  9. Potential role of ultrasound imaging in interstitial image based cervical cancer brachytherapy

    PubMed Central

    2014-01-01

    In 2012, more than 500,000 cases of cervical cancer were diagnosed worldwide. Over three quarters of these cases occur in less developed countries [1]. Advancements in image-guided brachytherapy are resulting in improved outcomes and reduced morbidity for women with this disease, but its worldwide adoption is hampered by lack of accessibility to advanced imaging techniques. Ultrasound is emerging as a potential option for tumor visualization, brachytherapy catheter placement, and treatment planning. While additional work is needed, ultrasound can potentially serve as the sole imaging modality for catheter insertion and planning. This paper will review our current knowledge on the use of ultrasound in interstitial brachytherapy treatment for cervical cancer. PMID:25097565

  10. Magnetic resonance imaging for planning intracavitary brachytherapy for the treatment of locally advanced cervical cancer.

    PubMed

    Oñate Miranda, M; Pinho, D F; Wardak, Z; Albuquerque, K; Pedrosa, I

    2016-01-01

    Cervical cancer is the third most common gynecological cancer. Its treatment depends on tumor staging at the time of diagnosis, and a combination of chemotherapy and radiotherapy is the treatment of choice in locally advanced cervical cancers. The combined use of external beam radiotherapy and brachytherapy increases survival in these patients. Brachytherapy enables a larger dose of radiation to be delivered to the tumor with less toxicity for neighboring tissues with less toxicity for neighboring tissues compared to the use of external beam radiotherapy alone. For years, brachytherapy was planned exclusively using computed tomography (CT). The recent incorporation of magnetic resonance imaging (MRI) provides essential information about the tumor and neighboring structures making possible to better define the target volumes. Nevertheless, MRI has limitations, some of which can be compensated for by fusing CT and MRI. Fusing the images from the two techniques ensures optimal planning by combining the advantages of each technique.

  11. Update on prostate brachytherapy: long-term outcomes and treatment-related morbidity.

    PubMed

    Kao, Johnny; Cesaretti, Jamie A; Stone, Nelson N; Stock, Richard G

    2011-06-01

    Current research in prostate brachytherapy focuses on five key concepts covered in this review. Transrectal ultrasound-guided prostate brachytherapy assisted by intraoperative treatment planning is the most advanced form of image-guided radiation delivery. Prostate brachytherapy alone for low-risk prostate cancer achieves lower prostate-specific antigen (PSA) nadirs than intensity-modulated radiotherapy (IMRT) or protons while maintaining durable biochemical control in about 90% of patients without late failures seen in surgically treated patients. As an organ-conserving treatment option, seed implant results in a lower rate of erectile dysfunction and urinary incontinence than surgery that has been validated in several recent prospective studies. Combined IMRT and seed implant has emerged as a rational and highly effective approach to radiation-dose escalation for intermediate- and high-risk prostate cancer. Preliminary results suggest that seed implantation may play a role in improving outcomes for historically poor-prognosis locally advanced and recurrent prostate cancers.

  12. Permanent Magnetic Bearing for Spacecraft Applications

    NASA Technical Reports Server (NTRS)

    Morales, Winfredo; Fusaro, Robert; Kascak, Albert

    2008-01-01

    A permanent, totally passive magnetic bearing rig was designed, constructed, and tested. The suspension of the rotor was provided by two sets of radial permanent magnetic bearings operating in the repulsive mode. The axial support was provided by jewel bearings on both ends of the rotor. The rig was successfully operated to speeds of 5500 rpm using an air impeller. Radial and axial stiffnesses of the permanent magnetic bearings were experimentally measured and then compared to finite element results. The natural damping of the rotor was measured and a damping coefficient was calculated.

  13. Permanent multipole magnets with adjustable strength

    SciTech Connect

    Halbach, K.

    1983-03-01

    Preceded by a short discussion of the motives for using permanent magnets in accelerators, a new type of permanent magnet for use in accelerators is presented. The basic design and most important properties of a quadrupole will be described that uses both steel and permanent magnet material. The field gradient produced by this magnet can be adjusted without changing any other aspect of the field produced by this quadrupole. The generalization of this concept to produce other multipole fields, or combination of multipole fields, will also be presented.

  14. Macroscopic simulation of isotropic permanent magnets

    NASA Astrophysics Data System (ADS)

    Bruckner, Florian; Abert, Claas; Vogler, Christoph; Heinrichs, Frank; Satz, Armin; Ausserlechner, Udo; Binder, Gernot; Koeck, Helmut; Suess, Dieter

    2016-03-01

    Accurate simulations of isotropic permanent magnets require to take the magnetization process into account and consider the anisotropic, nonlinear, and hysteretic material behaviour near the saturation configuration. An efficient method for the solution of the magnetostatic Maxwell equations including the description of isotropic permanent magnets is presented. The algorithm can easily be implemented on top of existing finite element methods and does not require a full characterization of the hysteresis of the magnetic material. Strayfield measurements of an isotropic permanent magnet and simulation results are in good agreement and highlight the importance of a proper description of the isotropic material.

  15. Prospects for nanoparticle-based permanent magnets

    SciTech Connect

    Balamurugan, B; Sellmyer, DJ; Hadjipanayis, GC; Skomski, R

    2012-09-01

    Magnetic nanoparticles smaller than similar to 15 nm in diameter and with high magnetocrystalline anisotropies K-1 >= 1 MJ m(-3) can be used as building blocks for next-generation permanent magnets. Advances in processing steps are discussed, such as self-assembly, alignment of the easy axes and appropriate nanostructuring that will enable the fabrication of densely packed nanopartide assemblies with improved permanent-magnet properties. This study also proposes an idealized nanocomposite structure for nanoparticle-based future permanent magnets with enhanced energy products. (C) 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  16. Quantifying IOHDR brachytherapy underdosage resulting from an incomplete scatter environment

    SciTech Connect

    Raina, Sanjay; Avadhani, Jaiteerth S.; Oh, Moonseong; Malhotra, Harish K.; Jaggernauth, Wainwright; Kuettel, Michael R.; Podgorsak, Matthew B. . E-mail: matthew.podgorsak@roswellpark.org

    2005-04-01

    Purpose: Most brachytherapy planning systems are based on a dose calculation algorithm that assumes an infinite scatter environment surrounding the target volume and applicator. Dosimetric errors from this assumption are negligible. However, in intraoperative high-dose-rate brachytherapy (IOHDR) where treatment catheters are typically laid either directly on a tumor bed or within applicators that may have little or no scatter material above them, the lack of scatter from one side of the applicator can result in underdosage during treatment. This study was carried out to investigate the magnitude of this underdosage. Methods: IOHDR treatment geometries were simulated using a solid water phantom beneath an applicator with varying amounts of bolus material on the top and sides of the applicator to account for missing tissue. Treatment plans were developed for 3 different treatment surface areas (4 x 4, 7 x 7, 12 x 12 cm{sup 2}), each with prescription points located at 3 distances (0.5 cm, 1.0 cm, and 1.5 cm) from the source dwell positions. Ionization measurements were made with a liquid-filled ionization chamber linear array with a dedicated electrometer and data acquisition system. Results: Measurements showed that the magnitude of the underdosage varies from about 8% to 13% of the prescription dose as the prescription depth is increased from 0.5 cm to 1.5 cm. This treatment error was found to be independent of the irradiated area and strongly dependent on the prescription distance. Furthermore, for a given prescription depth, measurements in planes parallel to an applicator at distances up to 4.0 cm from the applicator plane showed that the dose delivery error is equal in magnitude throughout the target volume. Conclusion: This study demonstrates the magnitude of underdosage in IOHDR treatments delivered in a geometry that may not result in a full scatter environment around the applicator. This implies that the target volume and, specifically, the prescription

  17. Brachytherapy structural shielding calculations using Monte Carlo generated, monoenergetic data

    SciTech Connect

    Zourari, K.; Peppa, V.; Papagiannis, P.; Ballester, Facundo; Siebert, Frank-André

    2014-04-15

    Purpose: To provide a method for calculating the transmission of any broad photon beam with a known energy spectrum in the range of 20–1090 keV, through concrete and lead, based on the superposition of corresponding monoenergetic data obtained from Monte Carlo simulation. Methods: MCNP5 was used to calculate broad photon beam transmission data through varying thickness of lead and concrete, for monoenergetic point sources of energy in the range pertinent to brachytherapy (20–1090 keV, in 10 keV intervals). The three parameter empirical model introduced byArcher et al. [“Diagnostic x-ray shielding design based on an empirical model of photon attenuation,” Health Phys. 44, 507–517 (1983)] was used to describe the transmission curve for each of the 216 energy-material combinations. These three parameters, and hence the transmission curve, for any polyenergetic spectrum can then be obtained by superposition along the lines of Kharrati et al. [“Monte Carlo simulation of x-ray buildup factors of lead and its applications in shielding of diagnostic x-ray facilities,” Med. Phys. 34, 1398–1404 (2007)]. A simple program, incorporating a graphical user interface, was developed to facilitate the superposition of monoenergetic data, the graphical and tabular display of broad photon beam transmission curves, and the calculation of material thickness required for a given transmission from these curves. Results: Polyenergetic broad photon beam transmission curves of this work, calculated from the superposition of monoenergetic data, are compared to corresponding results in the literature. A good agreement is observed with results in the literature obtained from Monte Carlo simulations for the photon spectra emitted from bare point sources of various radionuclides. Differences are observed with corresponding results in the literature for x-ray spectra at various tube potentials, mainly due to the different broad beam conditions or x-ray spectra assumed. Conclusions

  18. Evaluation of 101Rh as a brachytherapy source

    PubMed Central

    Ghorbani, Mahdi; Meigooni, Ali Soleimani

    2015-01-01

    Purpose Recently a number of hypothetical sources have been proposed and evaluated for use in brachytherapy. In the present study, a hypothetical 101Rh source with mean photon energy of 121.5 keV and half-life of 3.3 years, has been evaluated as an alternative to the existing high-dose-rate (HDR) sources. Dosimetric characteristics of this source model have been determined following the recommendation of the Task Group 43 (TG-43) of the American Association of the Physicist in Medicine (AAPM), and the results are compared with the published data for 57Co source and Flexisource 192Ir sources with similar geometries. Material and methods MCNPX Monte Carlo code was used for simulation of the 101Rh hypothetical HDR source design. Geometric design of this hypothetical source was considered to be similar to that of Flexisource 192Ir source. Task group No. 43 dosimetric parameters, including air kerma strength per mCi, dose rate constant, radial dose function, and two dimensional (2D) anisotropy functions were calculated for the 101Rh source through simulations. Results Air kerma strength per activity and dose rate constant for the hypothetical 101Rh source were 1.09 ± 0.01 U/mCi and 1.18 ± 0.08 cGy/(h.U), respectively. At distances beyond 1.0 cm in phantom, radial dose function for the hypothetical 101Rh source is higher than that of 192Ir. It has also similar 2D anisotropy functions to the Flexisource 192Ir source. Conclusions 101Rh is proposed as an alternative to the existing HDR sources for use in brachytherapy. This source provides medium energy photons, relatively long half-life, higher dose rate constant and radial dose function, and similar 2D anisotropy function to the Flexisource 192Ir HDR source design. The longer half-life of the source reduces the frequency of the source exchange for the clinical environment. PMID:26034499

  19. SU-F-BRA-04: Prostate HDR Brachytherapy with Multichannel Robotic System

    SciTech Connect

    Joseph, F Maria; Podder, T; Yu, Y

    2015-06-15

    Purpose: High-dose-rate (HDR) brachytherapy is gradually becoming popular in treating patients with prostate cancers. However, placement of the HDR needles at desired locations into the patient is challenging. Application of robotic system may improve the accuracy of the clinical procedure. This experimental study is to evaluate the feasibility of using a multichannel robotic system for prostate HDR brachytherapy. Methods: In this experimental study, the robotic system employed was a 6-DOF Multichannel Image-guided Robotic Assistant for Brachytherapy (MIRAB), which was designed and fabricated for prostate seed implantation. The MIRAB has the provision of rotating 16 needles while inserting them. Ten prostate HDR brachytherapy needles were simultaneously inserted using MIRAB into a commercially available prostate phantom. After inserting the needles into the prostate phantom at desired locations, 2mm thick CT slices were obtained for dosimetric planning. HDR plan was generated using Oncetra planning system with a total prescription dose of 34Gy in 4 fractions. Plan quality was evaluated considering dose coverage to prostate and planning target volume (PTV), with 3mm margin around prostate, as well as the dose limit to the organs at risk (OARs) following the American Brachytherapy Society (ABS) guidelines. Results: From the CT scan, it is observed that the needles were inserted straight into the desired locations and they were adequately spaced and distributed for a clinically acceptable HDR plan. Coverage to PTV and prostate were about 91% (V100= 91%) and 96% (V100=96%), respectively. Dose to 1cc of urethra, rectum, and bladder were within the ABS specified limits. Conclusion: The MIRAB was able to insert multiple needles simultaneously into the prostate precisely. By controlling the MIRAB to insert all the ten utilized needles into the prostate phantom, we could achieve the robotic HDR brachytherapy successfully. Further study for assessing the system

  20. MO-FG-210-00: US Guided Systems for Brachytherapy

    SciTech Connect

    2015-06-15

    Ultrasound (US) is one of the most widely used imaging modalities in medical practice. Since US imaging offers real-time imaging capability, it has becomes an excellent option to provide image guidance for brachytherapy (IGBT). (1) The physics and the fundamental principles of US imaging are presented, and the typical steps required to commission an US system for IGBT is provided for illustration. (2) Application of US for prostate HDR brachytherapy, including partial prostate treatments using MR-ultrasound co-registration to enable a focused treatment on the disease within the prostate is also presented. Prostate HDR with US image guidance planning can benefit from real time visualization of the needles, and fusion of the ultrasound images with T2 weighted MR allows the focusing of the treatment to the specific areas of disease within the prostate, so that the entire gland need not be treated. Finally, (3) ultrasound guidance for an eye plaque program is presented. US can be a key component of placement and QA for episcleral plaque brachytherapy for ocular cancer, and the UCLA eye plaque program with US for image guidance is presented to demonstrate the utility of US verification of plaque placement in improving the methods and QA in episcleral plaque brachytherapy. Learning Objectives: To understand the physics of an US system and the necessary aspects of commissioning US for image guided brachytherapy (IGBT). To understand real time planning of prostate HDR using ultrasound, and its application in partial prostate treatments using MR-ultrasound fusion to focus treatment on disease within the prostate. To understand the methods and QA in applying US for localizing the target and the implant during a episcleral plaque brachytherapy procedures.

  1. The changing landscape of brachytherapy for cervical cancer: a Canadian practice survey

    PubMed Central

    Phan, T.; Mula-Hussain, L.; Pavamani, S.; Pearce, A.; D’Souza, D.; Patil, N.G.; Traptow, L.; Doll, C.M.

    2015-01-01

    Background We documented changes in practice from 2009 to 2012 for cervical cancer brachytherapy in Canada. Methods Centres with gynecologic brachytherapy services were sent an e-mail questionnaire querying their 2012 practice. Responses are reported and compared with practice patterns identified in a similar survey for 2009. Results The response rate was 77% (24 of 31 centres). Almost all use high-dose-rate brachytherapy (92%); low-dose-rate brachytherapy has been completely phased out. Most continue to move patients from the site of applicator insertion to the radiation treatment simulation suite (75%) or to a diagnostic imaging department (29%), or both. In 2012, the imaging modalities used for dose specification were computed tomography [ct (75%)], magnetic resonance imaging [mri (38%)], plain radiography (21%), and cone-beam ct (8%). The number of institutions using mri guidance has markedly increased during the period of interest (9 vs. 1). Most respondents (58% vs. 14%) prescribed using guidelines from the Groupe Européen de Curiethérapie and the European Society for Therapeutic Radiology and Oncology, but they also used point A as a reference. Commonly used high-dose radiation regimens included 30 Gy in 5 fractions and 24 Gy in 3 fractions. Conclusions In Canada, image-guided brachytherapy for cervical cancer continues to evolve. Although ct-based imaging remains the most commonly used modality, many centres have adopted mri for at least 1 brachytherapy treatment. More centres are using fewer fractions and a slightly lower biologically effective dose, but are still achieving EQD2 (2-Gy equivalent) doses of 80–90 Gy in combination with external-beam radiation therapy. PMID:26628868

  2. Comparison of radiation shielding requirements for HDR brachytherapy using 169Yb and 192Ir sources.

    PubMed

    Lymperopoulou, G; Papagiannis, P; Sakelliou, L; Georgiou, E; Hourdakis, C J; Baltas, D

    2006-07-01

    169Yb has received a renewed focus lately as an alternative to 192Ir sources for high dose rate (HDR) brachytherapy. Following the results of a recent work by our group which proved 169Yb to be a good candidate for HDR prostate brachytherapy, this work seeks to quantify the radiation shielding requirements for 169Yb HDR brachytherapy applications in comparison to the corresponding requirements for the current 192Ir HDR brachytherapy standard. Monte Carlo simulation (MC) is used to obtain 169Yb and 192Ir broad beam transmission data through lead and concrete. Results are fitted to an analytical equation which can be used to readily calculate the barrier thickness required to achieve a given dose rate reduction. Shielding requirements for a HDR brachytherapy treatment room facility are presented as a function of distance, occupancy, dose limit, and facility workload, using analytical calculations for both 169Yb and 192Ir HDR sources. The barrier thickness required for 169Yb is lower than that for 192Ir by a factor of 4-5 for lead and 1.5-2 for concrete. Regarding 169Yb HDR brachytherapy applications, the lead shielding requirements do not exceed 15 mm, even in highly conservative case scenarios. This allows for the construction of a lead door in most cases, thus avoiding the construction of a space consuming, specially designed maze. The effects of source structure, attenuation by the patient, and scatter conditions within an actual treatment room on the above-noted findings are also discussed using corresponding MC simulation results.

  3. 30 CFR 817.132 - Cessation of operations: Permanent.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... INTERIOR PERMANENT PROGRAM PERFORMANCE STANDARDS PERMANENT PROGRAM PERFORMANCE STANDARDS-UNDERGROUND MINING ACTIVITIES § 817.132 Cessation of operations: Permanent. (a) The person who conducts underground mining... equipment, structures, or other facilities not required for continued underground mining activities...

  4. 30 CFR 817.132 - Cessation of operations: Permanent.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... INTERIOR PERMANENT PROGRAM PERFORMANCE STANDARDS PERMANENT PROGRAM PERFORMANCE STANDARDS-UNDERGROUND MINING ACTIVITIES § 817.132 Cessation of operations: Permanent. (a) The person who conducts underground mining... equipment, structures, or other facilities not required for continued underground mining activities...

  5. Dose rate in brachytherapy using after-loading machine: pulsed or high-dose rate?

    PubMed

    Hannoun-Lévi, J-M; Peiffert, D

    2014-10-01

    Since February 2014, it is no longer possible to use low-dose rate 192 iridium wires due to the end of industrial production of IRF1 and IRF2 sources. The Brachytherapy Group of the French society of radiation oncology (GC-SFRO) has recommended switching from iridium wires to after-loading machines. Two types of after-loading machines are currently available, based on the dose rate used: pulsed-dose rate or high-dose rate. In this article, we propose a comparative analysis between pulsed-dose rate and high-dose rate brachytherapy, based on biological, technological, organizational and financial considerations.

  6. [Partial breast irradiation technique with external beam radiation therapy and brachytherapy].

    PubMed

    Chand-Fouché, M-E; Lam Cham Kee, D; Gautier, M; Hannoun-Levi, J-M

    2016-10-01

    Accelerated Partial Breast Irradiation (APBI) appears to be an efficient therapeutic modality provided that it uses strict selection criteria and a reliable and well-managed technique. The techniques that enable to deliver postoperative APBI are interstitial brachytherapy, endocavitary brachytherapy and external beam radiation therapy. Once an appropriate selection of the candidates is made, each radiation technique needs an exact target volume definition and a strict compliance with its own dosimetric constraints. Results of ongoing randomized trials should increase our knowledge of all these parameters, and give us responses about the comparison of the different techniques.

  7. [Usefulness of urethral endoprosthesis in the management of urinary retention after brachytherapy for localized prostate cancer].

    PubMed

    Kerkeni, W; Chahwan, C; Lenormand, C; Dubray, B; Benyoucef, A; Pfister, C

    2014-03-01

    Brachytherapy is a possible treatment for localized low risk prostate cancer. Although this option is minimally invasive, some side effects may occur. Acute retention of urine (ARU) has been observed in 5% to 22% of cases and can be prevented in most cases by alpha-blocker treatment. Several alternatives have been reported in the literature for the management of ARU following brachytherapy: prolonged suprapubic catheterization, transurethral resection of the prostate and also intermittent self-catheterization. The authors report an original endoscopic approach, using urethral endoprosthesis, with a satisfactory voiding status.

  8. 78 FR 14122 - Revocation of Permanent Variances

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-04

    ... Occupational Safety and Health Administration Revocation of Permanent Variances AGENCY: Occupational Safety and Health Administration (OSHA), Labor. ACTION: Notice of revocation. SUMMARY: With this notice, OSHA is... into consideration these newly corrected cross references. DATES: The effective date of the...

  9. Nonuniform radiation damage in permanent magnet quadrupoles

    SciTech Connect

    Danly, C. R.; Merrill, F. E.; Barlow, D.; Mariam, F. G.

    2014-08-15

    We present data that indicate nonuniform magnetization loss due to radiation damage in neodymium-iron-boron Halbach-style permanent magnet quadrupoles. The proton radiography (pRad) facility at Los Alamos uses permanent-magnet quadrupoles for magnifying lenses, and a system recently commissioned at GSI-Darmsdadt uses permanent magnets for its primary lenses. Large fluences of spallation neutrons can be produced in close proximity to these magnets when the proton beam is, intentionally or unintentionally, directed into the tungsten beam collimators; imaging experiments at LANL’s pRad have shown image degradation with these magnetic lenses at proton beam doses lower than those expected to cause damage through radiation-induced reduction of the quadrupole strength alone. We have observed preferential degradation in portions of the permanent magnet quadrupole where the field intensity is highest, resulting in increased high-order multipole components.

  10. Characterizing hydrologic permanence in headwater streams

    EPA Science Inventory

    The presentation will be an overview of research to inform jurisdictional determinations for the Clean Water Act, in particular research that hydrographic comparisons of the extent and hydrologic permanence of headwater streams, indicator development, and an evaluation of a rapid...

  11. Micromachined permanent magnets and their MEMS applications

    NASA Astrophysics Data System (ADS)

    Cho, Hyoung Jin

    2002-01-01

    In this research, new micromachined permanent magnets have been proposed, developed and characterized for MEMS applications. In realizing micromachined permanent magnets, a new electroplating technique using external magnetic field and a bumper filling technique using a photolithographically defined mold with resin bonded magnetic particles have been developed. The newly developed micromachining techniques allow thick film-type permanent magnet components to be integrated to magnetic MEMS devices with dimensional control and alignment. Permanent magnet arrays with the dimensions ranging from 30 mum to 200 mum have been developed with an energy density up to 2.7 kJ/m3 in precisely defined forms in the micro scale. For the applications of the permanent magnets developed in this work, three novel magnetic MEMS devices such as a bi-directional magnetic actuator, a magnetically driven optical scanner, and a magnetic cell separator have been successfully realized. After design and modeling, each device has been fabricated and fully characterized. The bi-directional actuator with the electroplated permanent magnet array has achieved bi-directional motion clearly and shown good agreement with the analytical and simulated models. The optical scanner has shown linear bi-directional response under static actuation and stable bi-directional scanning performance under dynamic actuation. As a potential BioMEMS application of the developed permanent magnet, the prototype magnetic cell separator using the electroplated permanent magnet strip array has been proposed and demonstrated for magnetic bead patterning. In conclusion, new thick film-type, electroplated CoNiMnP and epoxy resin bonded Sr-ferrite permanent magnets have been developed and characterized, and then, three new magnetic MEMS devices using the permanent magnets such as a bi-directional magnetic actuator, an optical scanner and a magnetic cell separator have been realized in this research. The new micromachined

  12. Permanent magnet edge-field quadrupole

    DOEpatents

    Tatchyn, Roman O.

    1997-01-01

    Planar permanent magnet edge-field quadrupoles for use in particle accelerating machines and in insertion devices designed to generate spontaneous or coherent radiation from moving charged particles are disclosed. The invention comprises four magnetized rectangular pieces of permanent magnet material with substantially similar dimensions arranged into two planar arrays situated to generate a field with a substantially dominant quadrupole component in regions close to the device axis.

  13. Permanent education in health: a review

    PubMed Central

    Miccas, Fernanda Luppino; Batista, Sylvia Helena Souza da Silva

    2014-01-01

    OBJECTIVE To undertake a meta-synthesis of the literature on the main concepts and practices related to permanent education in health. METHODS A bibliographical search was conducted for original articles in the PubMed, Web of Science, LILACS, IBECS and SciELO databases, using the following search terms: “public health professional education”, “permanent education”, “continuing education”, “permanent education health”. Of the 590 articles identified, after applying inclusion and exclusion criteria, 48 were selected for further analysis, grouped according to the criteria of key elements, and then underwent meta-synthesis. RESULTS The 48 original publications were classified according to four thematic units of key elements: 1) concepts, 2) strategies and difficulties, 3) public policies and 4) educational institutions. Three main conceptions of permanent education in health were found: problem-focused and team work, directly related to continuing education and education that takes place throughout life. The main strategies for executing permanent education in health are discussion, maintaining an open space for permanent education, and permanent education clusters. The most limiting factor is mainly related to directly or indirect management. Another highlight is the requirement for implementation and maintenance of public policies, and the availability of financial and human resources. The educational institutions need to combine education and service aiming to form critical-reflexive graduates. CONCLUSIONS The coordination between health and education is based as much on the actions of health services as on management and educational institutions. Thus, it becomes a challenge to implement the teaching-learning processes that are supported by critical-reflexive actions. It is necessary to carry out proposals for permanent education in health involving the participation of health professionals, teachers and educational institutions. PMID:24789649

  14. Permanent magnet edge-field quadrupole

    DOEpatents

    Tatchyn, R.O.

    1997-01-21

    Planar permanent magnet edge-field quadrupoles for use in particle accelerating machines and in insertion devices designed to generate spontaneous or coherent radiation from moving charged particles are disclosed. The invention comprises four magnetized rectangular pieces of permanent magnet material with substantially similar dimensions arranged into two planar arrays situated to generate a field with a substantially dominant quadrupole component in regions close to the device axis. 10 figs.

  15. Optimizing parametrial aperture design utilizing HDR brachytherapy isodose distribution

    PubMed Central

    Chapman, Katherine L.; Ohri, Nitin; Showalter, Timothy N.

    2013-01-01

    Treatment of cervical cancer includes combination of external beam radiation therapy (EBRT) and brachytherapy (BRT). Traditionally, coronal images displaying dose distribution from a ring and tandem (R&T) implant aid in construction of parametrial boost fields. This research aimed to evaluate a method of shaping parametrial fields utilizing contours created from the high-dose-rate (HDR) BRT dose distribution. Eleven patients receiving HDR-BRT via R&T were identified. The BRT and EBRT CT scans were sent to FocalSim (v4.62)® and fused based on bony anatomy. The contour of the HDR isodose line was transferred to the EBRT scan. The EBRT scan was sent to CMS-XIO (v4.62)® for planning. This process provides an automated, potentially more accurate method of matching the medial parametrial border to the HDR dose distribution. This allows for a 3D-view of dose from HDR-BRT for clinical decision-making, utilizes a paperless process and saves time over the traditional technique. PMID:23634156

  16. Local recurrence of soft tissue sarcoma following brachytherapy.

    PubMed

    Gemer, L S; Trowbridge, D R; Neff, J; Lin, F; Reddy, E; Evans, R G; Hassanein, R

    1991-03-01

    Twenty-five patients with soft tissue sarcomas were treated with Ir192 implants following wide local excision at our institution between 1982 and 1987. External beam radiotherapy was given in addition to the implant in a majority of patients. The median follow-up in these 25 patients is 36 months (12 to 75 months). Twenty patients have had no evidence of local recurrence following their primary treatment (FFR = 80%). A multivariate analysis using stepwise logistic regression was used to predict failure in 3 years or less. Potential predictors examined included age, sex, tumor location, primary versus recurrent disease, grade, histology, surgical margins, implant only versus implant plus external beam, and a ratio of the volume of tissue which received 65 Gy (TV65) to the tumor volume (TV), that is (TV65/TV). The single variable which was significantly associated with local failure by 3 years was a TV65/TV of less than one. Once this variable was entered into the analysis, no other factor proved statistically significant. Our data suggest that when attempting local control of soft tissue sarcomas with brachytherapy, the volume of tissue receiving 65 Gy (TV65) from both implant and external beam must exceed the volume of the excised lesion (TV). Since the volume of a tumor can be readily determined prior to surgical excision either by CT or MRI scanning, pre-planning of the implant volume could potentially reduce the rate of local failure.

  17. Robotic Assistance for Ultrasound-Guided Prostate Brachytherapy

    PubMed Central

    Fichtinger, Gabor; Fiene, Jonathan P.; Kennedy, Christopher W.; Kronreif, Gernot; Iordachita, Iulian; Song, Danny Y.; Burdette, Everette C.; Kazanzides, Peter

    2016-01-01

    We present a robotically assisted prostate brachytherapy system and test results in training phantoms and Phase-I clinical trials. The system consists of a transrectal ultrasound (TRUS) and a spatially co-registered robot, fully integrated with an FDA-approved commercial treatment planning system. The salient feature of the system is a small parallel robot affixed to the mounting posts of the template. The robot replaces the template interchangeably, using the same coordinate system. Established clinical hardware, workflow and calibration remain intact. In all phantom experiments, we recorded the first insertion attempt without adjustment. All clinically relevant locations in the prostate were reached. Non-parallel needle trajectories were achieved. The pre-insertion transverse and rotational errors (measured with a Polaris optical tracker relative to the template’s coordinate frame) were 0.25mm (STD=0.17mm) and 0.75° (STD=0.37°). In phantoms, needle tip placement errors measured in TRUS were 1.04mm (STD=0.50mm). A Phase-I clinical feasibility and safety trial has been successfully completed with the system. We encountered needle tip positioning errors of a magnitude greater than 4mm in only 2 out of 179 robotically guided needles, in contrast to manual template guidance where errors of this magnitude are much more common. Further clinical trials are necessary to determine whether the apparent benefits of the robotic assistant will lead to improvements in clinical efficacy and outcomes. PMID:18650122

  18. TOPICAL REVIEW: Intravascular brachytherapy of the coronary arteries

    NASA Astrophysics Data System (ADS)

    Fox, R. A.

    2002-02-01

    This is a review of the relatively recently developed field of intravascular brachytherapy of coronary arteries. It presents a brief overview of the discipline of coronary angioplasty describing the problem of restenosis and discusses the potential for ionizing radiation to overcome this problem. It examines the various methods that have been used to irradiate the coronary arteries comparing their advantages and disadvantages. Special consideration is given to seeds and wires in the artery, radioactive liquids in the angioplasty balloon and radioactive stents. Passing reference is made to a number of other methods that have also been proposed, but which are not commonly used to irradiate the coronary arteries at present. The dosimetry of each of the major techniques is discussed and the data from different laboratories compared. Specific consideration is given to the need for centring of the radioactive source and the factors affecting the selection of a dose prescription. A brief review of recent clinical trials is followed by an examination of possible future directions in this field including the use of intravascular ultrasound to improve dosimetry, the use of gas-filled balloons to enhance the penetration of beta-emitting sources and the use of gamma-emitting stents to overcome the problems associated with edge restenosis.

  19. Developing a dose-volume histogram computation program for brachytherapy.

    PubMed

    Panitsa, E; Rosenwald, J C; Kappas, C

    1998-08-01

    A dose-volume histogram (DVH) computation program was developed for brachytherapy treatment planning in an attempt to benefit from the DVH's ability to present graphically information on 3D dose distributions. The program is incorporated into a planning system that utilizes a pair of orthogonal radiographs to localize the radiation sources. DVHs are calculated for the volume of tissue enclosed by an isodose surface (e.g. half the value of the reference isodose). The calculation algorithm is based on a non-uniform random sampling that gives a denser point distribution at the centre of the implants. Our program was tested and proved to be fast enough for clinical use and sufficiently accurate (i.e. computation time of 20 s and less than 2% relative error for one point source, for 100,000 calculation points). The accuracy improves when a larger calculation point number is used, but the computation time also increases proportionally. The DVH is presented in the form of a simple graph or table, or as Anderson's 'natural' DVH graph. The cumulative DVH tables can be used to extract a series of indexes characterizing the homogeneity and the dose levels of the distribution in the treatment volume and the surrounding tissues. If a reference plan is available, the DVH results can be assessed relative to the reference plan's DVH.

  20. Quality of life of oropharyngeal cancer patients treated with brachytherapy.

    PubMed

    Teguh, David N; Levendag, Peter C; Kolkman-Deurloo, Inger-Karine; van Rooij, Peter; Schmitz, Paul I M

    2009-03-01

    Brachytherapy (BT) is a highly conformal (accurate clinical target volume delineation, no planning target volume margin) radiotherapy technique; the radioactive source, guided by afterloading catheters, is implanted into the heart of the tumor. The localized high dose of radiation enables high tumor control rates and, because of rapid dose fall-off, sparing of the adjacent normal tissues. At the Erasmus Medical Center, excellent results were observed: 5-year local regional control of 84%, 5-year disease-free survival of 59%, and 5-year overall survival of 64%. Therefore, in the case of moderately sized tumors, for well-trained, skillful physicians, BT is the therapy of choice (if technically feasible). However, side effects are not totally negligible, partly because of the cumulative dose of BT and the first series of 46/2 Gy. However, patients treated with BT still have a better swallowing-related quality of life, which might improve further if summation of BT and the first series of 46/2 Gy, as well as autocontouring of the neck levels, are realized. So far, there is no significant relationship between the -quality index of the BT implants and local control/overall survival and/or quality of life.

  1. WE-G-BRC-02: Risk Assessment for HDR Brachytherapy.

    PubMed

    Mayadev, J

    2016-06-01

    Failure Mode and Effects Analysis (FMEA) originated as an industrial engineering technique used for risk management and safety improvement of complex processes. In the context of radiotherapy, the AAPM Task Group 100 advocates FMEA as the framework of choice for establishing clinical quality management protocols. However, there is concern that widespread adoption of FMEA in radiation oncology will be hampered by the perception that implementation of the tool will have a steep learning curve, be extremely time consuming and labor intensive, and require additional resources. To overcome these preconceptions and facilitate the introduction of the tool into clinical practice, the medical physics community must be educated in the use of this tool and the ease in which it can be implemented. Organizations with experience in FMEA should share their knowledge with others in order to increase the implementation, effectiveness and productivity of the tool. This session will include a brief, general introduction to FMEA followed by a focus on practical aspects of implementing FMEA for specific clinical procedures including HDR brachytherapy, physics plan review and radiosurgery. A description of common equipment and devices used in these procedures and how to characterize new devices for safe use in patient treatments will be presented. This will be followed by a discussion of how to customize FMEA techniques and templates to one's own clinic. Finally, cases of common failure modes for specific procedures (described previously) will be shown and recommended intervention methodologies and outcomes reviewed.

  2. In vivo dosimetry: trends and prospects for brachytherapy

    PubMed Central

    Rosenfeld, A; Beddar, S; Tanderup, K; Cygler, J E

    2014-01-01

    The error types during brachytherapy (BT) treatments and their occurrence rates are not well known. The limited knowledge is partly attributed to the lack of independent verification systems of the treatment progression in the clinical workflow routine. Within the field of in vivo dosimetry (IVD), it is established that real-time IVD can provide efficient error detection and treatment verification. However, it is also recognized that widespread implementations are hampered by the lack of available high-accuracy IVD systems that are straightforward for the clinical staff to use. This article highlights the capabilities of the state-of-the-art IVD technology in the context of error detection and quality assurance (QA) and discusses related prospects of the latest developments within the field. The article emphasizes the main challenges responsible for the limited practice of IVD and provides descriptions on how they can be overcome. Finally, the article suggests a framework for collaborations between BT clinics that implemented IVD on a routine basis and postulates that such collaborations could improve BT QA measures and the knowledge about BT error types and their occurrence rates. PMID:25007037

  3. Long-term results of endobronchial brachytherapy: A curative treatment?

    SciTech Connect

    Hennequin, Christophe . E-mail: christophe.hennequin@sls.ap-hop-paris.fr; Bleichner, Olivier; Tredaniel, Jean; Quero, Laurent; Sergent, Guillaume; Zalcman, Gerard; Maylin, Claude

    2007-02-01

    Purpose: To evaluate outcomes after high-dose-rate endobronchial brachytherapy (HDR-EBBT) for limited lung carcinoma. Methods: A total of 106 patients with endobronchial lung cancer and not eligible for surgery or external beam radiotherapy, without nodal or visceral metastases, were treated with HDR-EBBT. They had developed disease relapse after surgery (n = 43) or external beam radiotherapy (n = 27) or had early lung cancer with respiratory insufficiency (n = 36). Treatment consisted of six fractions of 5 or 7 Gy, usually delivered 1 cm from the source. Results: The complete histologic response rate, evaluated at 3 months after HDR-EBBT, was 59.4%. At 3 and 5 years, the local control, overall survival, and cause-specific survival rates were 60.3% and 51.6%, 47.4 and 24%, and 67.9 and 48.5%, respectively. Factors significantly associated with local failure were high tumor volume (tumor length >2 cm, bronchial obstruction >25%, tumor visibility on CT scan) and previous endoscopic treatment. Cause-specific survival, but not overall survival, was significantly associated with local control, probably because of the high rate of deaths not related to lung cancer. Five deaths were attributed to the HDR-EBBT procedure (two from fatal hemoptysis and three from bronchial necrosis). Conclusion: High-dose